Added non-trivial beam checker specialization, refactored parameter name declarations
don't prune off-beam if heap is empty, handles cases where sequence lengths differ by > beam
fix logic for beam pruning, added unit testing for beam
throw -O via CMAKE_CXX_FLAGS
tweak the timing test -- holy crap it's way faster with -O
inline path_lessthan and visited_lessthan
unit testing for beam width and edit_alignment