Merged revs 1820-1920 from trunk

git-svn-id: https://subversion.assembla.com/svn/portaudio@1923 0f58301d-fd10-0410-b4af-bbb618454e57
CMake: Added PA_WDMKS_NO_KSGUID_LIB to WDMKS and solution folders
WDMKS: Support for default device (see caveat for input devices though in ScanDeviceInfos)
       Added possibility to set channel mask


git-svn-id: https://subversion.assembla.com/svn/portaudio@1924 0f58301d-fd10-0410-b4af-bbb618454e57