BUG:330661 Save multi-sensor configuration correctly

Big rewrite & cleanup of the sensors/libpaintop code...

The KisDynamicSensorList class is gone and KisCurveOption now tracks
all sensors. The KisMultiSensorModel doesn't own the data it is a model
for anymore everything is tracked by KisCurveOption.

Conflicts:
	krita/plugins/paintops/spray/kis_spray_paintop_settings_widget.cpp
	krita/plugins/paintops/spray/kis_sprayop_option.cpp
	krita/plugins/paintops/spray/spray_brush.cpp
	krita/plugins/paintops/spray/spray_brush.h