New plugin to handle role groups

Role groups will be part of the ACI system. It will let one create broad
categories of permissions. Things like: helpdesk, user admin, group admin,
whatever.

install/updates/rolegroup.update

@@ -0,0 +1,5 @@
+# Add the rolegroup container
+
+dn: cn=rolegroups,cn=accounts,$SUFFIX
+add:objectClass: nsContainer
+add:cn: rolegroups