A somewhat cleaner DRUP implementation
Adding DRUP debugging
Better bracketing
Adding DRUP debugging
Fixing popcnt() for Windows

Fixes #77
Fixing option renaming for non-DRUP system
Requiring DRUP for DRUP_DEBUG
Don't ask for DRUP by default when testing
Add DRUP into CMakeLists
Don't update lits, it's removed from *here*