Requirements:
different persons with different admin rights should handle the same posix group.

Traps:
- currently posix groups only allow posix accounts (and not groups) as members
- system request for eg. gid numbers are ask with simelimit = 1, so every group can only be once in LDAP

Solution:
"Master Groups". Master groups have an attribute "suseSearchFilter". All member attributes that matches the search filter get merged and saved as members of the master group. Manual changes to the members of the master group will be overwritten. Other attributes of the master group can be modified manually.
