had to (hopefully temporarily) remove Concrete.rsc, since it is
completely out of date with the current parse tree format. From now on
we parse all library modules to find such issues.
many parsing regression tests still fail, but now it's visible which.
fixed parser errors in box Parse module
fixed parse error
fixing lots of parse errors and missing imports
another bunch of parse errors
Merge branch 'master' of git@github.com:cwi-swat/rascal.git