Index names are not case sensitive on any platform.

Column, index, stored routine, and event names are not case sensitive
on any platform, nor are column
aliases.
Compared table's dotted path instead of table absolute name.
Added hashcode and equals methods for MySQLIndexMetaDataImpl
Compared table dotted path instead of absoluted name.
Fixed bug: isNull should be part of index entry, considering it is related to column, so we just provide a method to get the value from column.

1.Removed isNull method from MySQLIndexMetaData interface.
2.Added isNull method to IndexMetaData.Entry interface.
Updated hashCode and equals methods of ForeignKeyMetaDataImpl
Updated DB_Compare_Criteria