This adds another option I use in my project with cx_Freeze, code signing. This allows you to use bdist_dmg and have the app bundle get code signed properly before being compressed and ready for distribution. Supported options are codesign_identity and codesign_entitlements. The first is required if code signing and the second for users who are sandboxing their application. Other codesign options could be added as requested in the future, but these are the common ones.
This pull request also re-adds documentation for include_frameworks and custom_plist that seem to have been lost in a merge somewhere.
I've also cleaned up many things that pyflakes and pylint were complaining about in macdist.py. I've removed some unused modules, removed unnecessary backslashes, fixed lots of spacing and indents, and wrapped some lines that were over 80 characters. Aside from a couple of code complexity warnings, I no longer get any warnings in python-mode for vim with these changes. Hurray!