Compare string version of types in MySQL

See: https://groups.google.com/d/msg/yesodweb/M1hGNedIvng/VY6gTaNCmt8J
parseType for MySQL keeps original type
MySQL migration: add missing columns #233
Get column type from COLUMN_TYPE instead of DATA_TYPE

Addresses:
https://groups.google.com/d/msg/yesodweb/M1hGNedIvng/5EVWd5U36wUJ
Better round-tripping of types
Merge branch 'better-mysql-migration'