Port english version of managing groups for REST.
Port english version of managing groups page for REST.
Port english version of changing a group name page for REST.
Port english version of changing a group owner page for REST.
Port english version of adding group members page for REST.
Insert removing group members page into adding group members for REST.
Port english version of listing groups page for REST.
Port english version of listing group member page for REST.
Merge pull request #54 from shinsuke-nara/group

Port english version managing group section for REST.