Remove leading "x" from xor clause when searching for max variable
Using get_max_var_from_clause in regression test
OOps, typo, the line is called 'line' not 'l'
There was a uppercase-lowercase problem, fixed
Empty resolvents can now be counted with a different function
Removing unused variable
Moving test CNFs
Adding minimal unit tests

Thanks to Lukas Prokop for nudging me along the way :)
Oops, the basic test ended up as assumptions test
Fixing indentation, empty lines
Pass the solver configuration by value

It's fast enough
Renaming the test modules
Forgot to update setLit1->setLit2 when updating lit1()->lit2()

Also, setLit2->setLit3 when lit2->lit3 got updated. Thanks to Martin
Maurer for spotting this!

Fixes #102