Modify registers at the end of a cycle to ensure all dependencies have
been computed.
Finish up plumbing; it works! (See rest of the commit message for details.)

Big commit:
* Use Parsec to parse inline input and check that it is well-formatted
* OptArg -> ReqArg in getParams (which is the Right Thing (TM))
* Correct handling of command line arguments
* The tests work!
Merge branch 'master' of github.com:threonorm/simulisp

Conflicts:
	haskell/InputParser.hs