- renamed the FluidSetting functions to ChangeSetting so that they can be used as a generic means to change music player options without overloading the virtual function table for each minor thing.
- pass Printf as a parameter to the MIDI renderer to uncouple it from the main GZDoom code.
- throw exceptions when setting up the renderer fails so that this can be handled consistently for all construction errors here.
- delete FluidSynth handles before the constructor aborts.
The organization here is now the same as for the Timidity++ device, i.e. it is the device owning the instruments to give better control over their lifecycle.
