Add audiofile as third-party dependency
Add project to build libaudiofile
Link libaudiofile against MrsWatson

Not quite working yet, but getting rather close.
Remove SampleSourceAiff

This never really worked and will be replaced by audiofile later.
Move audiofile sample source stuff to single file

Really simplifies the code in the internal WAVE sample source, which will
remain in the project even after the migration.
Remove SampleSourceFlac, replaced by audiofile
Build audiofile with cmake
Switch to our fork of audiofile
Make flac optional within audiofile
Enable audiofile by default
Expose convertPcmDataToSampleBuffer method

Used by audiofile reader
Fix method for reading data via audiofile
Switch to windows-fixup branch