FsmState: added diameter property
Arrow: stop at FsmState limit
MainWindow: added "add state" button
FsmState: add flag ItemSendsGeometryChanges (fix transitions display bug)
Switched Arrow to FsmTransition class
Added test code to FsmScene, FsmState,

Added rubber band mode for selection.

Antialiasing hint done on GraphicsView

Added FsmGraphicsView to support scene scrolling (ctrl-drag) and zooming (ctrl-scroll)

New icon.
Added fixed statename to FsmState class
state standalone paint with selection dependent background color
added empty status bar.
new state names controlled by FsmScene
FsmGraphicsView zoom with Ctrl+Scroll, horizontal scroll with Alt+Scroll (normal vertical scroll with scroll...)