Creates a new group.

By default the group is created in the internal realm. To import an
LDAP group, set import_from_ldap_group_setting to the name of the LDAP
group setting that covers it and name to the group's name in the
directory. The directory matches name with its own comparison rule
for the group name attribute, which ignores case for cn and the other
standard name attributes; on a directory that compares names exactly,
use the group name exactly as the directory spells it. The group is
created in the ldap realm under the directory's name in lowercase, the
same as a group imported from the LDAP Groups screen. LDAP login keeps
its members in sync with the directory. members
cannot be set together with import_from_ldap_group_setting. To import
every group of an LDAP group setting at once, use the Refresh LDAP Group
Settings API.

Security: Requires admin privileges.