OS X changes
Merge branch 'master' of https://github.com/open-ephys/GUI
Merge branch 'master' of https://github.com/open-ephys/GUI
Avoid using unopened files.

When many channels are selected for recording a race condition can cause a crash by writing to a file that has not been opened yet.
Added Open Ephys data files to .gitignore
Added files for RHD2000 DataThread
GUI can now communicate with RHD2000 eval board (but no data transfer yet)
Updated RHD2000Thread; thread streams data at up to 30 kHz, but the samples still look like junk
RHD2000Thread is working for 32 channels
Removed check for multiple Intan Boards in ProcessorGraph
Converted Clock away from OpenGL
ControlPanel is now free of OpenGL
InfoLabel is now free of OpenGL calls
EditorViewportButton is now free of OpenGL calls
OpenGLCanvases no longer make OpenGL calls
ProcessorList rendering is now acceptable
Updated JUCE library
Removed deprecated use of setContentComponent
Updated MidiMessage/MidiBuffer code to allow spikes to be sent as MIDI messages
Removed custom tab drawing