"Replace" API for UFFields in a UFGroup

When saving an entire profile form, we will need to update all the UFField rows within a given UFGroup.

There is an API action, "replace", which does a search (eg "match on uf_group_id=5") and then replaces records en masse (doing any insert/update/delete operations). However, it's not clear if this works with UFField.

The main deliverable is a working demonstration of calling cj.crmAPI('UFField','replace'...). We will likely need some patches for the UFField API/BAO. X may have already put some patches in this branch:

http://svn.civicrm.org/civicrm/branches/trunk.profile/