Pull - I from kleinerm for PTB BETA RELEASE "Sex, Lies and Video" SP1

A pull with the work so far. Only Screen's for OSX are up to date.
This mostly to pull in the 10 bpc framebuffer improvements and dithering fixes for AMD pre-HD-5000 GPUs.
Also some robustness improvements for OSX 10.9 stimulus onset - none had any effect, actually.
Marktertrackerplugin support on Linux + dc1394 engine.
Octave 3.8 support on OSX, removal of < 3.8 support.
Minor improvements and fixes here and there.