Removed forced settings in runtests

Tests that require USE_I18N, LOGIN_URL or certain MIDDLEWARE_CLASSES
should be decorated appropriately.
Ran a test that closes the database connection outside of a transaction.
Switched the admin to use @transaction.atomic.
Ported layermapping for autocommit.
Adjusted query counts to account for new savepoints.
Avoided closing the database connection within a transaction.

Refs #9437.
Merge branch 'master' into deprecate-comments