Tagging the 2.1.1 release of the dune-istl module.
release tag
revert accidental commit 1320
merge rev 1082 from trunk
fix FS #581 (thanks to Markus)
patch 1008 ('inform about a bug in OpenMPI') merged from the trunk
remove WML from Makefiles (not needed in tar balls)
version 1.1
added maintainer address.
Merged README changes from trunk