Improve description layout. Improve coloring and add legend in help.

Improve description layout. Improve coloring and add legend in help.

Convert monkey patching to class inheritance for OptionParser usage in:
commit_queue.py, gclient.py and trychange.py.

Monkey patching confuses the hell out of pylint.

R=jochen@chromium.org
BUG=

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=213423

[M-A Ruel, 2013-07-24 13:44:53]

All I wanted was to add a legend and all I got is this lousy CL.

$ git cl help status
Usage: git_cl.py status [options] 

Show status of changelists.

Colors are used to tell the state of the CL unless --fast is used:
  - Green   LGTM'ed
  - Blue    waiting for review
  - Yellow  waiting for you to reply to review
  - Red     not sent for review or broken
  - Cyan    was committed, branch can be deleted

Also see 'git cl comments'.

Options:
  -h, --help     show this help message and exit
  -v, --verbose  Use 2 times for more debugging info
  --field=FIELD  print only specific field (desc|id|patch|url)
  -f, --fast     Do not retrieve review status

[jochen (gone - plz use gerrit), 2013-07-24 13:48:45]

lgtm

[commit-bot: I haz the power, 2013-07-24 13:54:54]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/maruel@chromium.org/19552004/2001

[commit-bot: I haz the power, 2013-07-24 13:56:50]

Change committed as 213423