Fixes issues with building Citra on OSX

Only Rect is in the namespace for now; the rest of common should be added in the future

After adding FindGLEW.cmake to externals, the variable call for the GLEW include path needed to be revised.
Append flags on OSX, rather than overwrite them.
I realized that GCC_COMPILE_FLAGS was changed to CMAKE_CXX_FLAGS mistakenly, so both were changed to a more platform-independent name.

Changed QGL version to 3,2 in order to be less restrictive, yet it should still change up to 4,1 on OSX on Qt5.

Changes for clarity of comments, removed redundant compiler flags.

ARM VFP support - integrated from SkyEye

- removed HLE::CallMCR function (was pointless)

- fixed some compiler issues with xscale_copro when porting code to Windows
- fixed some #include's

- added initial VFP code from skyeye

Various fixes/improvements to HLE of 3DS services, mostly cleans up GSP call decoding

Update FlipFramebuffer - makes converting the raw framebuffer slightly faster

Less calculations + fix

- added a helper function for getting command buffer for services
- fixed bug where GSP DMA was incorrectly being done in DataSynchronizationBarrier (instead of gsp_TriggerCmdReqQueue)