Updated gen_bunny to use amqp_client version 3.3.1.
- Updated rebar.config.
- Updated bunny_util and bunny_util_tests.

The AMQP client params record [amqp_params] is now deprecated.
The correct record should be [amqp_params_network] or [amqp_params_direct]
depending of the desired connection.  (direct or network.)

(Long Version...)
============== amqp_client changes details ==============

In function amqp_connection:start(AmqpParams),
  AmqpParams must be [amqp_params_network] or [amqp_params_direct].

------------------------------------------------------------------------------
- The OLD amqp_connection:start()
------------------------------------------------------------------------------

    start(Type, AmqpParams) ->
        {ok, _Sup, Connection} = amqp_connection_sup:start_link(Type, AmqpParams),
        Module = case Type of direct  -> amqp_direct_connection;
                              network -> amqp_network_connection
                 end,
        try Module:connect(Connection) of
            ok -> {ok, Connection}
        catch
            exit:{Reason = {protocol_version_mismatch, _, _}, _} ->
                {error, Reason};
            exit:Reason ->
                {error, {auth_failure_likely, Reason}}
        end.

------------------------------------------------------------------------------
- The LATEST (3.3.1) amqp_connection:start()
------------------------------------------------------------------------------

    start(AmqpParams) ->
        ensure_started(),
        AmqpParams1 =
            case AmqpParams of
                \#amqp_params_network{port = undefined, ssl_options = none} ->
                    AmqpParams#amqp_params_network{port = ?PROTOCOL_PORT};
                \#amqp_params_network{port = undefined, ssl_options = _} ->
                    AmqpParams#amqp_params_network{port = ?PROTOCOL_SSL_PORT};
                _ ->
                    AmqpParams
            end,
        {ok, _Sup, Connection} = amqp_sup:start_connection_sup(AmqpParams1),
        amqp_gen_connection:connect(Connection).