SQL setting auth-type & return codes

[Phil Mayers]

I was going to knock out a quick concept patch but I see it's not a 
trivial patch; before I make the effort to code it I thought I'd check:

It seems useful for the sql module to set the return code to 
RLM_MODULE_REJECT if the Auth-Type gets set to reject - the specific use 
case I have is an unlang policy like so:

authorize {
  preprocess

  sql

  if ("%{reply:MyStatus}" !~ /Active|Guest/) {
    reject
  }

  # ...some more stuff
}

...however inside the SQL I have groups with

  id | groupname | attribute | op | value
----+-----------+-----------+----+--------
   2 | staff     | MyStatus  | =  | Active
   3 | banned    | Auth-Type | := | Reject

...and it would be nice if members of the "banned" group stopped 
processing early.

At the moment the SQL module only returns FAIL, NOTFOUND or OK.

Thoughts?