rename the 'vertex handles' to 'grid communication handles'

they were never vertex specific and always meant for grid
communication with aribtrary entities. (specified by the mapper.)
fix a few GCC signedness and pedantic warnings
Bring the joy of parallelism also to the common decoupled stuff. Fix the pressure matrix assembly in parallel if faces are visited only once. Can be tested with test/decoupled/2p/test_parallel in dumux-devel. Reviewed by Markus.

Dumux-Svn-Revison: 9434
Ported-By: Andreas Lauser <andreas.lauser@iws.uni-stuttgart.de>
Enable parallelism for decoupled 2p2c. Requires AMGBackend and patches for pdelab and istl. Can therefore only be used from devel (currently). Reviewed by Benjamin.

Dumux-Svn-Revison: 9414
Ported-By: Andreas Lauser <andreas.lauser@iws.uni-stuttgart.de>
Parallelize also adaptive and multiphysics 2p2c. Reviewed by Benjamin.

Dumux-Svn-Revison: 9433
Ported-By: Andreas Lauser <andreas.lauser@iws.uni-stuttgart.de>
Communicate subdomain information in the multiphysics models if run in parallel. This fixes subdomain definition if subdomain enters ghost cells.

Dumux-Svn-Revison: 9439
Ported-By: Andreas Lauser <andreas.lauser@iws.uni-stuttgart.de>
Enable the MPFA methods to run in parallel. Reviewed by Markus.

Dumux-Svn-Revison: 9440
Ported-By: Andreas Lauser <andreas.lauser@iws.uni-stuttgart.de>
added the package names for SUSE installation

Dumux-Svn-Revison: 9497
Ported-By: Andreas Lauser <andreas.lauser@iws.uni-stuttgart.de>