made grid snap favour grid points closer to origin, in case of ties
Merge branch 'master' of https://github.com/skieffer/ortho

resolved minor conflict

Conflicts:
	libcola/cc_nonoverlapconstraints.cpp
wrote coincidence prediction
Merge branch 'master' of https://github.com/skieffer/ortho
debugging coincidence prediction...
debugged coincidence checking
debugging overlap prevention...
Merge branch 'master' of https://github.com/skieffer/ortho