L1ConfigurationBuilder should disable onRehash when disabling L1

The L1ConfigurationBuilder (rightly) breaks when l1 is disabled and l1 onrehash is enabled. Unfortunately when a configuration is inherited via read() from a previous configuration where l1 was enabled (and onrehash enabled implicitly because of this), the user is forced to call L1ConfigurationBuilder.disable().disableOnRehash(), which is a bit redundant. This also breaks AS7.