### Please describe the problem.

After following the (new) Android installation instructions, git-annex is not on `$PATH`, therefore literal `git annex` commands fail.
I'm sure this is trivially fixed by enhancing the install script so that it modifies `$PATH` in the termux profile, or similar.

### What steps will reproduce the problem?

1. Follow the instructions at https://git-annex.branchable.com/Android/ up to `sh git-annex-install`
2. Observe that the install succeeds
3. Try the next step: `git annex webapp`
4. Observe the error `git: 'annex' is not a git command. See 'git --help'.`
5. Observe that it works when using `./git-annex.linux/git-annex` instead

### What version of git-annex are you using? On what operating system?

6.20180927-gc5b6c55af on Android 8.1.0 (OxygenOS 5.1.5) on a OnePlus 5T (A5010).

### Please provide any additional information below.

[[!format sh """
# If you can, paste a complete transcript of the problem occurring here.
# If the problem is with the git-annex assistant, paste in .git/annex/daemon.log
% sh -x git-annex-install                                                                                                             [20/4719]
+ set -e                                                                                                                                       
+ uname -m                                                                                                                                     
+ arch=arm64                                                                                                                                   
+ url=https://downloads.kitenet.net/git-annex/linux/current/git-annex-standalone-arm64.tar.gz                                                  
+ echo Installing dependencies with termux pkg manager...                                                                                      
Installing dependencies with termux pkg manager...                                                                                             
+ pkg install git wget tar coreutils proot                                                                                                     
Hit:1 https://termux.net stable InRelease                                                                                                      
Reading package lists... Done                                                                                                                  
Building dependency tree                                                                                                                       
Reading state information... Done                                                                                                              
19 packages can be upgraded. Run 'apt list --upgradable' to see them.                                                                          
Reading package lists... Done                                                                                                                  
Building dependency tree                                                                                                                       
Reading state information... Done                                                                                                              
coreutils is already the newest version (8.30-1).                                                                                              
git is already the newest version (2.19.1).                                                                                                    
proot is already the newest version (5.1.107-18).                                                                                              
tar is already the newest version (1.30-1).                                                                                                    
wget is already the newest version (1.19.5-1).                                                                                                 
0 upgraded, 0 newly installed, 0 to remove and 19 not upgraded.
+ echo Downloading git-annex...
Downloading git-annex...                
+ cd                                         
+ wget -O- https://downloads.kitenet.net/git-annex/linux/current/git-annex-standalone-arm64.tar.gz                                            
+ tar zx                                        
--2018-10-21 23:41:37--  https://downloads.kitenet.net/git-annex/linux/current/git-annex-standalone-arm64.tar.gz                              
Resolving downloads.kitenet.net... 66.228.36.95, 2600:3c03::f03c:91ff:fe73:b0d2                                                               
Connecting to downloads.kitenet.net|66.228.36.95|:443... connected.
HTTP request sent, awaiting response... 200 OK
Length: 64590742 (62M) [application/x-gzip]
Saving to: ‘STDOUT’        
                     
-                                   100%[==================================================================>]  61.60M  2.51MB/s    in 81s     
                             
2018-10-21 23:42:59 (778 KB/s) - written to stdout [64590742/64590742]
                                 
+ git-annex.linux/git-annex version                                  
Running on Android.. Adding git-annex to PATH for you, and tuning for optimal behavior.                                                       
git-annex version: 6.20180927-gc5b6c55af
build flags: Assistant Webapp Pairing S3(multipartupload)(storageclasses) WebDAV Inotify DBus DesktopNotify ConcurrentOutput TorrentParser Mag$
cMime Feeds Testsuite                               
dependency versions: aws-0.19 bloomfilter-2.0.1.0 cryptonite-0.25 DAV-1.3.2 feed-1.0.0.0 ghc-8.2.2 http-client-0.5.12 persistent-sqlite-2.8.1.$
 torrent-10000.1.1 uuid-1.3.13 yesod-1.6.0
key/value backends: SHA256E SHA256 SHA512E SHA512 SHA224E SHA224 SHA384E SHA384 SHA3_256E SHA3_256 SHA3_512E SHA3_512 SHA3_224E SHA3_224 SHA3_$
84E SHA3_384 SKEIN256E SKEIN256 SKEIN512E SKEIN512 BLAKE2B256E BLAKE2B256 BLAKE2B512E BLAKE2B512 BLAKE2B160E BLAKE2B160 BLAKE2B224E BLAKE2B224
BLAKE2B384E BLAKE2B384 BLAKE2S256E BLAKE2S256 BLAKE2S160E BLAKE2S160 BLAKE2S224E BLAKE2S224 BLAKE2SP256E BLAKE2SP256 BLAKE2SP224E BLAKE2SP224 $
HA1E SHA1 MD5E MD5 WORM URL                                        
remote types: git gcrypt p2p S3 bup directory rsync web bittorrent webdav adb tahoe glacier ddar hook external                                
operating system: linux aarch64                                                                                                               
supported repository versions: 3 5 6                                                                                                          
upgrade supported from repository versions: 0 1 2 3 4 5
+ echo git-annex is successfully installed.                           
git-annex is successfully installed.                    
+ echo Now running termux-setup-storage, to let git-annex access system storage.                                                              
Now running termux-setup-storage, to let git-annex access system storage.                                                                     
+ termux-setup-storage                         
+ echo Installation complete.                                                                                                                 
Installation complete.                                                                                                                        
% git annex webapp              
git: 'annex' is not a git command. See 'git --help'.
# End of transcript or log.
"""]]

### Have you had any luck using git-annex before? (Sometimes we get tired of reading bug reports all day and a lil' positive end note does wonders)

Yes, lots of luck over the years :-)  This is the final little tweak required to get it working for me on Android.

> [[fixed|done]] --[[Joey]]
