PSPNG ldap-group provisioning is case-sensitive

Group-Member attributes (member in Active Directory, uidmember in posix group, uniquemember in groupofuniquenames, etc) are found three different ways:
1) Read from the Group object [Always]
2) Read from the member objects [Often]
3) Generated by a template [Sometimes]

Sometimes there are case differences when #1 is compared to results from #2 & #3 and pspng 2.3.0's default settings compares them case-sensitively, causing large, unnecessary ldap operations. -Most ldap-group attributes are not case sensitive.

This problem should be fixed by adding a pspng configuration setting for ldap-group provisioning that specifies if member attributes should be compared case-sensitively (default: false)