Fixed issues with XOR and parameterized functions

This fixes a significant number of issues blocking fully working homomorphic functions.  There's still some work to do adding unit tests
for binary versions of the functions, cleaning up some commented code, and optimizing compose.

- Fixed bug in extension routine in Monomial class. Still needs some love to make sure bounds checks are respected.

- Modified private key to no longer use hacky parameterization static factory.

- Added unary and test back in.