Integrate ROI selection to Photom

Added:
- drawing mode group in control window, includes roi selection and pattern dropdown, pattern spacing boxes, and deletion of shapes
- scrollable widget behavior for laser control window
- attributes to LaserMarkerWindow class to contain shapes

Changed:
- how displaying shapes are handled. shape/drawings are displayed by calling self.update() now
- shapesUpdate signal to notify of new shapes added
- updated mouse event handling to track and store Shape objects