if it was provided. Always check and graduate, regardless of shadow status.

Don't clobber sml_type when converting SLAPI mods

modifications to be applied by the backend atomically with a modify
RDN request.

Handle updating of RDN values in frontend.

Code that calls a backend's be_modrdn should call slap_modrdn2mods(op, rs)
before invoking the backend and cleanup with slap_mods_free( op->orr_modlist, 1 ).
See do_modrdn() for an example.

ACL checks when modifying user-modifiable attributes as non-root user.

update/referral checks

global overlays need to set o_bd = frontendDB to return the error in case no database can be selected