Feature OSX FAT

This pull request has FAT libs built for OSX. The 64 bit version uses ofAVFoundationVideoPlayer by @obviousjim and @prisonerjohn. Two #defines have been added, TARGET_32 and TARGET_64 for OSX. These can be defined later for other operating systems so that the TARGET_32 and TARGET_64 is universal. There are two target for the OF static lib, one 32 and one 64bit.

A sample app is located in apps/devApps/FAT_OSX/

I had trouble finding the correct compiler flags for Assimp, right now the FAT lib is ~65Mb, compared to the current 32 bit lib size of ~7Mb.

It would be great to get this into the OF repo as a test branch so people can contribute. Right now users can choose between 32/64 bit by setting the Architecture in the build settings. It must be changed in both the current project build settings and in the top left corner (My Mac 32/64 bit). 

See this thread for more info: https://github.com/openframeworks/openFrameworks/issues/2016#issuecomment-34201809