Function gm_boilerplate::sync_boilerplate

pub fn sync_boilerplate<Fut, F, C>(
    mx: Mx, 
    reply: SyncReply, 
    f: F
) -> MatrixFuture<Vec<(Room<'static>, C)>> where
    Fut: Future<Item = Vec<C>, Error = MatrixError> + 'static,
    F: FnMut(Mx, &Room<'static>, &Event) -> Fut,
    C: 'static,