need ability to do case-insensitive compare

[balmas]

Reported by Bob Gorman: I notice that the Gold Standard comparison feature is finding some students in error because their labels contain different capitalization than the standard. This is not good. Take a look at sentence 3 in the following link. The student's answers for equitatus and interger seem to be wrong merely because of orthography (Sbj/SBJ and Atr/ATR). Something for you to think about over the holidays. :-)