changed a requirement during PCNF construction (in RobinsonToLK): it is enough that a subsequent of the clause c dervied from the projection formula f is derived in subsequent calls. whatever is missing is weakened in later. also changed RobinsonToLK s.t. the full end-sequent is weakened in if we did not need all the formulas to simulate the resolution refutation. fixes issue 247.

git-svn-id: http://gapt.googlecode.com/svn/trunk/source@1733 85d21ef8-add0-11de-ae77-5bfb9c5a3f34
fixing a bug in reduceHolToFol

git-svn-id: http://gapt.googlecode.com/svn/trunk/source@1734 85d21ef8-add0-11de-ae77-5bfb9c5a3f34