[SSSD] [PATCH] Remove DP process

[Simo Sorce]

I couldn't get to sleep early this night, so I decided to give a try and
remove the DP.

The job turned out to be much easier than I expected.
I've tested it with 3 backends (local + 2 native ldap ones), and tested
euth against the krb backend.
All seem to work but please review carefully as this is a change to a
core piece of the machinery.

Simo.