Get the list of users of a particular group

[malishahi]

We need to get the list of users of a particular group in a realm. For that, we need to proxy to the following Keycloak admin api.

http://www.keycloak.org/docs-api/3.4/rest-api/index.html#_groups_resource

Get users Returns a list of users, filtered according to query parameters GET /admin/realms/{realm}/groups/{id}/members

Type	Name	Description	Schema
Path	idrequired		string
Path	realmrequired	realm name (not id!)	string
Query	firstoptional	Pagination offset	integer(int32)
Query	maxoptional	Maximum results size (defaults to 100)	integer(int32)