Fixed bug: "PRIMARY" can not be used as index name of fk and should be ingored.
Exposed getSchemaName method for schema
[TODO] 1 test about fk which need to be done.
Fixed Bug: Before comparing two databases, we have to make sure they both exist.
Fixed Bug: Forgot to add space before key word.
Refactored builders to reduce query times with database server.
Updated databaseName to schemaName
Added 1 exception message
Fixed Bug: Sorted foreign key list when comparing