* EXreaction/feature/migrations: (48 commits) [feature/migrations] Remove default values from necessary parameters [feature/migrations] Revert unrelated changes to functions.php [ticket/9737] Fix some comments [ticket/9737] Fix a few minor things in migrations [feature/migrations] Make sure migration data not done before running data step [feature/migrations] Function to populate the migrations table (for install) [feature/migrations] Function effectively_installed() in migrations [feature/migrations] Make load_migrations recursive (optionally) [feature/migrations] Make the test depends_on methods static [feature/migrations] Make depends_on static to call it without dependencies [feature/migrations] install/database_update_migrations.php [feature/migrations] Move test.php -> install/database_update_migrations.php [feature/migrations] Store depends on in the database (serialized) [feature/migrations] Revert method completed [feature/migrations] Basic reverting test [feature/migrations] Test for calling a step multiple times [feature/migrations] Creating revert method to attempt reverting a migration [feature/migrations] Some comments in db_tools [feature/migrations] Reverse data functionality [feature/migrations] Comment ... Conflicts: phpBB/install/schemas/firebird_schema.sql phpBB/install/schemas/mssql_schema.sql phpBB/install/schemas/mysql_40_schema.sql phpBB/install/schemas/mysql_41_schema.sql phpBB/install/schemas/oracle_schema.sql phpBB/install/schemas/postgres_schema.sql phpBB/install/schemas/sqlite_schema.sql