Bash completion about possible usernames from: - environment variable SVN_BASH_USERNAME  - ~/.subversion/auth/... files    (if activated by adding 'username' to SVN_BASH_COMPL_EXT). Costly completions are not activated by default.
Bash completion about possible usernames from:
- environment variable SVN_BASH_USERNAME 
- ~/.subversion/auth/... files 
  (if activated by adding 'username' to SVN_BASH_COMPL_EXT).
Costly completions are not activated by default.

* tools/client-side/bash_completion:
  _svn_read_hashfile(): new function to "parse" svn hash files
  _svn(): --username option values handling


git-svn-id: f8a4e5e023278da1e04e203c7fe051e3c4285d88@867069 13f79535-47bb-0310-9956-ffa450edef68

wbond/subversion,wbond/subversion,YueLinHo/Subversion,YueLinHo/Subversion,wbond/subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,wbond/subversion,wbond/subversion,wbond/subversion,YueLinHo/Subversion,YueLinHo/Subversion,wbond/subversion