mod_storage_s3: Enable connection pooling added in latest trunk Speed boost, something like a 30% improvement with http://localhost Small risk of failed requests due to limits on number of requests per connection or timeouts.

This module lets you block connections to any remote servers not on a
whitelist.

``` {.lua}
modules_enabled = {
    -- other modules --
    "s2s_whitelist",

}
s2s_whitelist = {
    "example.org",
}
```