Add FPS/VideoFormat to name conversion helpers
Add DecodeDeviceId helper with DStr targets
Update config modified callbacks with disable/autoselection semantics

Autoselection is only implemented for frame rate as it doesn't make
sense to autoselect the video format (Any fills the role of library
supplied autoselection) or the resolution (it may make sense to
implement resolution matching based on the current transformation
settings in the future though)
Implement frame rate autoselection for win-dshow device update
Add name for VideoFormat::Any
Add FPS entries "Highest" and "Match OBS FPS" for win-dshow