Nodes now contain tokens

Nodes cannot be anymore Activated or Deactivated.
When a node is selected, a new property menu appears.
This menu let the user add tokens to the node.

Compile does not work for the moment.
Nouveaux sprites pour test
New options for the window containing the game
Tokens replaces active nodes + randInt expression

The nodes now contain tokens which can move along the graph. Tokens
contain parameters so that those parameters move along with the token.
A boolean expression of an arc can recognize a token.
A node can contain multiple tokens.
A token moveing through an arc activates the consequences of that arc.
The consequences now include
- delete the token moving through the arc
- editing that token
- add a new token on any arc

New boolean expression : randInt(Variable,Int) which unify Variable
with any integer between 0 and Int-1.