Allow to select the database other than ‘default’ on migration
Throw DBSettingException when the connection pool is not found
Merge pull request #36 from tototoshi/feature/specify-dbname-on-migration

Allow to select the database other than ‘default’ on migration
Merge pull request #37 from tototoshi/feature/avoid-npe-on-migration

Throw DBSettingException when the connection pool is not found