Update mkqrt.py script, add more icons
Add more functionality in player, shortcuts for basic playback control actions,
volume custom icon updates, "mute" button.
Merge together volume indicator and "mute" button
Update "About" menu item
Intercept key events for VideoPlayer to provide additional control shortcuts
Move settings related logic to corresponding  module
Use to alternative way to bind shortcuts in player
Modify create_button to create QToolButton if optional 'action' argument was given
Add license