* Use the simplifying node factory and the type checking node factory when parsing...

* Use the simplifying node factory and the type checking node factory when parsing the CVC format via the main method. I haven't changed the c-interface to simplify as it build.
* Remove some explicit type checks in the CVC parser. Since the type checking node factory type checks each node it creates, there's no reason to have so many explicit type checks. So I've removed some of them.

git-svn-id: https://stp-fast-prover.svn.sourceforge.net/svnroot/stp-fast-prover/trunk/stp@764 e59a4935-1847-0410-ae03-e826735625c1