Stuff To Be Implemented/Fixed
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 - Add Arc
 - Add Polygon
 - Manipulate Dimension
 - Object connections
 - Group selection (kind done, needs more work though)
 - Take movement code out of Objects and put it into top level Container
 - Fix snap to grid to honor both states (right now, it's a weird mix of states)
 - Add OSD routines so they don't have to be implemented in Objects
 - Add OSD to Object creation
 - Add layers
 - Add blocks
 - Add page layout
 - Add pen color/style/width to Objects
 - Add fill/hatch to Objects
 - Fix zooming to be more intuitive
 - Add other Dimension types, like radial, diametric, leader
 - Add Ellipse
 - Add Spline
 - Add Text