CRM-10667 Port Drupal 7 version of permission clauses to drupal 6 &
remove smart group resolution from permission clause.
This is all handled in 4.3 through a re-write of permission classes 
and the removal of smart group resolution from them
CRM-12209 fix group visibility ETA 4.3
Merge branch '4.2-master' of ssh://git@github.com/fuzionnz/civicrm.git into 4.2-master