Using a helper function to clean up clause statistics printing
Helper function for statistics checker
Using helper functions for irredundant clause dumping
Using helper function in redundant clause dumping
Using helper functions to print clause stats
Updating renumbering to use helper functions
Moving algo to where it belongs
Better placement of function call
Moving DRUP to a separate header file
Making DRUP into a polymorphic system, with improved clause handling

This alleviates the problem of having to check if 'drup' is NULL and
removes the need for the repetitive ' << "0\n"'.
Making DRUP part of the normal solver