Code review comment for lp://staging/~bac/juju-quickstart/brew-commands

Reviewers: mp+221412_code.launchpad.net,

Message:
Please take a look.

Description:
Include installation steps for OS X.

A slight re-factoring was done to move platform-specific steps from
app.py to
platform_support.py.

Also ProgramExit was moved to utils.py. Many of the test still refer to
app.ProgramExit. That change can be made post-review so as to not
clutter up
the actual changes, if desired.

https://code.launchpad.net/~bac/juju-quickstart/brew-commands/+merge/221412

(do not edit description out of merge proposal)

Please review this at https://codereview.appspot.com/102870043/

Affected files (+200, -40 lines):
   A [revision details]
   M quickstart/app.py
   M quickstart/manage.py
   M quickstart/platform_support.py
   M quickstart/tests/test_app.py
   M quickstart/tests/test_platform_support.py
   M quickstart/utils.py