Application compiles and runs, with some caveats. Full list of changes:
- minor changes related to Qt4->Qt5 API differences
- Replaced calls to Carbon framework by Cocoa
- Removed registering of AE event handler. Seems to be done
automatically in Qt5.
- temporarily removed Podcast functionality, pending (presumably)
complete re-write due to Quicktime being obsolete in newer OS X
versions.
- Created OBCocoa namespace, and associated files src/core/OBCocoa.h/.mm, to
handle OS X - specific system calls. Currently used only by
UBApplication, but can in the future provide a useful interface between
the cocoa framework and OB, to avoid having too much OSX-specific code
in various files