Change OPL-update so that it uses Taxonomy2 which cross-lists sections of the library.  Also makes sure DBsubject/chapter/section are case sensitive.
Merge pull request #414 from jwj61/OPL-update-update

Opl update update
Merge branch 'release/2.9' of https://github.com/openwebwork/webwork2 into develop

Conflicts:
	bin/OPL-update