'Installs a new image on the server
:param server_id: Id of the server
:rtype: ``str``
:param image_id: Id of the image (Server Appliance)
:rtype: ``str``
:param password: New password for the server
:return:    Instance of class ``Node``
:rtype:     :class: `Node`'

def ex_reinstall_server_image(self, server_id, image_id, password=None):

    body = {'id': image_id}
    if (password is not None):
        body['password'] = password
    response = self.connection.request(action=('servers/%s/image' % server_id), data=body, method='PUT')
    return self._to_node(response.object)
