Reformatted to Google Java Style guide

No code changes, this change just gets the formatting consistent by using 2-space indentation instead of tabs or 4-space.
Added OS X support for the automatic deck import feature

The implementation could be improved slightly by using CGWindowListCreateDescriptionFromArray but I couldn't get that working, so I used the less efficient CGWindowListCopyWindowInfo instead. Works just fine now!
Added help link for Decks tab
Merge pull request #398 from gtch/master

OS X support for the automatic deck import feature