Renamed update_contents to update_images and added a new update_contents method that calls update_images when the have_objects_changed member is set to True.
Changing the map sets the have_objects_changed member to True.
MousePressed callbacks now need to accept and additional "button" argument that determines the mouse button that was pressed.
Right clicking on a map with a layer selected now only removes the object from the clicked cell.
Added "mouse_dragged" to the editor listener callbacks.
When "dragging" the mouse over the map while the static objects toolbar is active the objects will now be placed on the cells the mouse is moved over.
The map can now be scrolled by holding the left mouse button.
Pressing space now resets the camera to position (0, 0)
Removed debug and falsely committed code.