[merge from SAMBA_3_0]

[merge from SAMBA_3_0]

Merging smbgroupedit into 'net groupmap'.  Not entirely done.
Need to check on where the privilege code is sitting
and update the docs.

Examples:

root# bin/net help groupmap
net groupmap add
  Create a new group mapping
net groupmap modify
  Update a group mapping
net groupmap delete
  Remove a group mapping
net groupmap list
  List current group map

# bin/net groupmap add
Usage: net groupmap add rid=<int> name=<string> type=<domain|local|builtin> [comment=<string>]

# bin/net groupmap delete
Usage: net groupmap delete name=<string|SID>

# bin/net groupmap modify
Usage: net groupmap modify name=<string|SID> [comment=<string>] [type=<domain|local>]
(This used to be commit 0fd28bc3a803ca1ec3dcd8cc6236d4ecc3134584)