implement ilike() operator

[Mike Bayer]

the "ilike" operator is present in sql.Operators. lets wire it up, and have ansisql.py produce "lower(x) like lower('foo')" (or somehow lowercase the right-side bind param) for those DBs that dont have ilike (or in mysql, perhaps just produce "like"?).

[jek]

that's still more or less correct for mysql- LIKE uses the column collation, which is most likely lowercase but no guarantee. lower() might even noop in that case. i think the "most correct" way using COLLATE would require knowing the column character set, which is untenable.

[Mike Bayer]

this is so ready to be done and comes up all the time....its just a few op()s and some unit tests. time to do it !

[Mike Bayer]

diff:@4053:4055

[Mike Bayer]

Removing milestone: 0.4.3 (automated comment)