Ticket 48272 - ADDN Sytle prebind plugin
    
    Fix Description:  This plugin allows a unique entry that matches some filter
    to bind with "user1" -> "uid=user1,ou=People,dc=example,dc=com".
    
    For the user to bind:
    
    * Only a single entry may be mapped from the filter, else it is considered a failure.
    * The entry must belong under a specific suffix
    * The user@domain.com maps the domain to a subconfig which maps to a suffix
      to search underneath.
    
    https://fedorahosted.org/389/ticket/48272
    
    Author: wibrown
    
    Review by: mreynolds, nhosoi (thank you both!)