Remove QTMultimedia
portaudiocpp in CMake
Herp derp -- InputDevice dialog shows PortAudio host APIs
input device list
Text box for sample rate
Hurray, reading from PortAudio!

And it doesn't use 100% CPU like Qt does.

Future plan: make PortAudio implementation stable enough that
PulseAudio implementation can be removed.
Merge branch 'portaudio'