server_groups.go
func (c *Client) UpdateServerGroup(updateServerGroup *ServerGroupOptions) (*ServerGroup, error) {
	group := new(ServerGroup)
	_, err := c.MakeApiRequest("PUT", "/1.0/server_groups/"+updateServerGroup.Id, updateServerGroup, &group)
	if err != nil {
		return nil, err
	}
	return group, nil
}
func (c *Client) UpdateServerGroup(updateServerGroup *ServerGroupOptions) (*ServerGroup, error) {
	group := new(ServerGroup)
	_, err := c.MakeApiRequest("PUT", "/1.0/server_groups/"+updateServerGroup.Id, updateServerGroup, &group)
	if err != nil {
		return nil, err
	}
	return group, nil
}
// UpdateServerGroup updates an existing server groups's attributes. Not all
// attributes can be changed (such as Id).
//
// Specify the server group you want to update using the ServerGroupOptions Id
// field.
//
// To change group memberships, use AddServersToServerGroup,
// RemoveServersFromServerGroup and MoveServersToServerGroup.