test boss_cache_adapter_ets

In your CB app, you can enable ets cache to test now.

    {cache_adapter, ets},
    {ets_maxsize, 4194304}, %% 4*1024*1024
    {ets_threshold, 0.85},
    {ets_weight, 30}
    {cache_enable, true},
    %%    {cache_servers, [{"localhost", 11211, 1}]},
    {cache_exp_time, 60},