added an ambiguous proof example for hlk. we decided that this kind of ambuguity is not relevant at the moment

git-svn-id: http://gapt.googlecode.com/svn/trunk/source@1456 85d21ef8-add0-11de-ae77-5bfb9c5a3f34
added cli command loadHLK

git-svn-id: http://gapt.googlecode.com/svn/trunk/source@1457 85d21ef8-add0-11de-ae77-5bfb9c5a3f34
Implemented a script to test the cut-introduction algorithm on the TSTP proofs. Added debug printing to the cut-introduction algorithm (but don't know how to use them... seems like everything is printed every time). Implemented a new method in solvePropositional that will only return if the sequent is provable or not. Implemented super-set function for grammars.

git-svn-id: http://gapt.googlecode.com/svn/trunk/source@1458 85d21ef8-add0-11de-ae77-5bfb9c5a3f34
reorganisation of ivy and sexpressions

git-svn-id: http://gapt.googlecode.com/svn/trunk/source@1459 85d21ef8-add0-11de-ae77-5bfb9c5a3f34