Setting tag MyPLC-4.3-29

- Added "SetRole()" so that db-config.d/ scriplets can insert roles
into the DB.
- Added the root ssh key handling support back into plc.d/ssh and the
default xml file.  This should be identical to the way it was in
rc12.
- Added support in the db-config.d/01-init script to register the root
ssh public key with the default administrator.  In this way the root
ssh key will make it into the root account on the nodes by means of
NodeManager's specialaccounts plugin.