illumos gate

Outside of unnecessary branch iterations when choosing a parent branch,
pbchk could make use of environment variables to allow automating use of it.

If this branch tracks a remote branch, return the remote branch which is tracked.

Otherwise find and compare the url of each remote to PBCHK_PARENT_URL,
or to 'git://github.com/illumos/illumos-gate' if not defined.

If no match, default to PBCHK_PARENT or 'origin/master' if not defined.

No change if '-b <branch-name>' is specified.

Example uses:

richard@omnis:/home/richard/src/illumos-gate$ git pbchk

Current branch: test_tracked
Choosing tracked parent: upstream/master

richard@omnis:/home/richard/src/illumos-gate$ git pbchk

Current branch: pbchk1
Remotes available:
     illumos-core => git://github.com/gdamore/illumos-core.git
   illumos-joyent => git://github.com/joyent/illumos-joyent
   illumos-omnios => git://github.com/omniti-labs/illumos-omnios.git
           origin => ssh://git@github.com/risto3/illumos-gate
         upstream => git://github.com/illumos/illumos-gate
Choosing 'upstream/master' as parent.

Comments:
These comments are not valid bugs:
  inform branch info git-pbchk

richard@omnis:/home/richard/src/illumos-gate$ PBCHK_PARENT_URL=none git pbchk

Current branch: pbchk1
Remotes available:
     illumos-core => git://github.com/gdamore/illumos-core.git
   illumos-joyent => git://github.com/joyent/illumos-joyent
   illumos-omnios => git://github.com/omniti-labs/illumos-omnios.git
           origin => ssh://git@github.com/risto3/illumos-gate
         upstream => git://github.com/illumos/illumos-gate
Choosing 'origin/master' as default parent.

Comments:
These comments are not valid bugs:
  inform branch info git-pbchk

richard@omnis:/home/richard/src/illumos-gate$ PBCHK_PARENT_URL=git://github.com/joyent/illumos-joyent git pbchk

Current branch: pbchk1
Remotes available:
     illumos-core => git://github.com/gdamore/illumos-core.git
   illumos-joyent => git://github.com/joyent/illumos-joyent
   illumos-omnios => git://github.com/omniti-labs/illumos-omnios.git
           origin => ssh://git@github.com/risto3/illumos-gate
         upstream => git://github.com/illumos/illumos-gate
Choosing 'illumos-joyent/master' as parent.

Comments:
These comments are not valid bugs:
  inform branch info git-pbchk

Copyrights:
usr/src/lib/libc/port/threads/pthr_barrier.c: no copyright claim for current year found
usr/src/lib/libc/port/threads/pthr_mutex.c: no copyright claim for current year found
usr/src/lib/libc/port/threads/pthr_cond.c: no copyright claim for current year found
usr/src/lib/libc/port/threads/pthr_rwlock.c: no copyright claim for current year found