Avoid calling BigInteger.mod for small operations on prime fields
Performance improvements for Fp points:
- Replace multiplications by small constants with additions
- Implement 2P + Q optimization from paper by Ciet, Joye et. al.
Avoid final call to twice()
Use the new method twicePlus in left-to-right EC multiplications
some cleanup, fixes and new tests
Merge remote-tracking branch 'upstream/master'