A new custom software mixer, supports playing streams at any rate, which is needed to emulate the directsound SetFrequency effects (when a ride malfunctions and the music slows down and stops).  The speex resampler is added for this.  Currently samples can be played and their volumes and looping set on an arbitrary number of channels.  Support for FLAC and other streaming formats can be added.
Merge branch 'master' of https://github.com/IntelOrca/OpenRCT2

Conflicts:
	projects/openrct2.vcxproj.filters
cmake build
cmake build
Merge branch 'master' of https://github.com/zsilencer/OpenRCT2
0x006BB9FF, 0x006BC2F3, mixer edit, completed 0x6BB76E
Merge branch 'master' of https://github.com/IntelOrca/OpenRCT2

Conflicts:
	projects/openrct2.vcxproj.filters
	src/window_scenery.c
0x006BBC6B, hook
Merge branch 'master' of https://github.com/IntelOrca/OpenRCT2
hook
gcc fix?
0x00401AF3, 0x006BC6D8, corrections
0x0069A5A0, 0x006AC988, couple fixes
Merge branch 'master' of https://github.com/zsilencer/OpenRCT2 into zsilencer-master

Conflicts:
	projects/openrct2.vcxproj.filters
Merge branch 'zsilencer-master'