Implemented QSV encoder

Added libmfx (opensource part of Intel Media SDK dispatcher and headers)
Merge pull request #201 from palana/master

QSV (hardware) encoder support
Fixed a memory leak in x264 encode path and minor improvements for QSV encoder
Moved yuv buffer mutliplexing to QSV encoder and implemented a more asynchronous pipeline
Added basic CPU time profiling support

Note that threaded yuv conversion now creates two profiler nodes
Improved timestamp handling in QSV encoder
made some minor alterations to a few artificial size limiations.  saying 32 is too big is fine, but anyone who goes below 16 seriously needs to find a better way of doing things.
updated git ignore.
Merge remote-tracking branch 'origin/master'
one minor bug with sizing to 16 or below
Fixed propagation of x264 fallback in case QSV is selected
Missing include for VS2012, fixes #203
Fix game capture aspect ratio handling properly, new and improved, etc.
Fix tearing issue with multithreaded optimizations and QSV
got rid of some pesky whitespace
made a slight tweak to get the proper DTS values in QSV frame output
Only output one frame at a time
Improved tracking of buffers in use
Use QSV API 1.6 if available
Code cleanup and unsquishing, sanitized DTS handling