Updated the visualization module
Updated Trilinos support to version 11.2.3
Added NASA almond to shapes.py
Removed the method Grid::boundarySegmentCount().

It has never worked, relying on a feature not supported by Dune FoamGrid.
And we have never needed it yet.
Restored compatibility with AHMED compiled with Bebendorf's complex number class.
Merge branch 'master' of https://github.com/bempp/bempp into coalesced_operators