Tulip 4.7.0 is available

This is essentialy a maintenance release with many bug fixes and improvements in:
- the OpenGL rendering engine,
- the GUI, especially in the
* Adjacency Matrix,
* Geographic,
* Histogram,
* Parallel Coordinates,
* Scatter plot
dedicated views.

Two new features have been also added;
a new edge drawing algorithm Curve Edges can be used to compute quadratic or cubic bezier paths for edges,
and the new rendering property viewFontAwesomeIcon allowing to use one of the many predefined icons (about 600 are available) of the free Font Awesome iconic font (by David Gandy - see http://http://fontawesome.io) for the rendering every node of a graph.