code: function ContactsGroupsMembersDelete(options, groupId, contactId) {
      ActionAbstract.call(this, options);
      this._groupId = groupId;
      this._contactId = contactId;
  }
docs: unpin contact from the group
  @see http://dev.smsapi.pl/#!/contacts%2Fgroups/contactsDelete
  @param {Object} options
  @param {String} groupId
  @param {String} contactId
  @extends ActionAbstract
  @constructor