Added:
- Basic object resizing
- Basic support for mouse cursor

Changed:
- Objects now have "resize buttons". Removed the original selection
marks.
- Changed the way we draw objects w.r.t. the storage of coordinates. At
the end of drawing, each objects now resets itself to our standard
orientation.

Fixed:

Todo:
- Determine how to resize ellipses
- Resizing lines
- Import text
-