Breakup INSTALLED_APPS

Breakup INSTALLED_APPS so that the settings can be read for which apps
are developed alongside the main app. This is useful so that they can
be tested together using the custom test runner.
Modify TestRunner to only test OTM2-related apps
Update fabfile to test all MANAGED_APPS

So that we make sure to test them often. In order to _not_ test them,
you must specify a test filter explicitly.
Merge pull request #226 from steventlamb/ops/util_updates

Update TestRunner to only test OTM2 related apps