Remove suspicious uses of toLower and toUpper

Particularly around identifiers. This was a manual search/remove for uses of toLowerCase(), toUpperCase() and String.CASE_INSENSITIVE_ORDERING. 

High level strategy is that the AIS contains the real casing and any insensitivity comes from the parser. This was basically what was in place. Offenders were Columnar.add/getColumn and Table/Group.add/getIndex, which lower-cased on the way in and for look-up. Note that REST/JSON didn't muck with anything before (casing is as exactly given) and that hasn't changed.

Two types of test fallout: laziness (relying on the AIS casing help) and Map ordering (indexes with equivalent costs). Nothing otherwise interesting.