KNOWN BUGS to fix:
    - Matching : the induced subgraph from an instance of a LHS in a model should be the same as the instance of LHS (no more edges).
    => all port of a rule not connected to the arrow node or an edge in LHS **must not be connected** in the model. This is not tested at the moment

    - Strategy : when computing F_1 \ F_2, when removing a node from F_1, its incident edges should be removed too to avoid dandling edges.

Strategy plugin: 
- Add strategy edge when using all(T). At least add something which works like a strategy edge (to know the beginning and end of a strategy)
- Add support for ppick(F_1, ..., F_n, \Pi)


- Add clear and complete support for Attach, Connect, Ports
- Map properties to be consistent with the paper:
    * Colour => viewColor
    * Name => viewLabel
    * Self => id
    * Type => ????


Import plugin:
- add support to import graph/rule from tlpx files

Export plugin:
- Add support to export all rules in a single tlp file

Perspective:
- Add in the validation widget for each node and port the list of checked properties for matching

TODO:
    - matching algorithm: test only edges between portnodes and not all edges from the Tulip Graph
    - matching algorithm: Avoid to match edges again in VerifyIso

IMPROVEMENTS:
- use the new tlp::selectShortestPaths instead of bool PorgyTlpGraphStructure::graphIsASimplePath(Graph *graph)
- use GlGraphRenderingParameters::setDisplayFilteringProperty() instead of my ugly code for displaying the parts of a rule (LHS, RHS)
