Converted solution to VS 2013.
Retargeted SharpAvi and Sample projects to .NET 4.5. Added SharpAvi.Fx35 project targeting .NET 3.5 CP.
Changed assembly version to 1.2.
Audio stream (without data yet).
Writing audio stream header and data (PCM format only).
Audio recording in sample app.
Added counters of written frame/blocks. Tweaked audio stream header.
Synchronization of video/audio writes in sample app.