Placing object and select uses unzoomed coordinates
Petrinet components now appear when inserted when zoomed

* Repaint entire petri net, this probably isn't the most
  efficient way
Fix arc head drawing

* ZOOM_GROW was accidentally removed from x component of
  graphics translate
Tidy up unused methods
Use JLayer to implement zooming

* Create a ZoomUI which intercepts painting where it applies
  the scaling matrix,
  it also intercepts mouse events and redirects them to their new
  zoomed coordinates

* Create a drag manager which handles both dragging when the mouse is
  in the component and from the selection manager when dragging has
  exceeded the component bounds because the mouse moves too fast

* Removed methods that are no longer needed from the ZoomController
Remove TODO
Zoom in and out now updates zoom dialog
Dirty hack to get zooming working with dragging and placing componetns

* call root.repaint in updatebounds method
  this is a terrible fix but I cant figure out how else to do it
Fix copy and paste not working with zoom ui
Avoid pasting components twice
* Only paste if pasteInProgress is set
Add scrolling back in

* Its a bit horrid because ZoomUI now needs the petrinet but
  I couldnt get JLayer to be wrapped in a scroll
  had to do it the other way around