mod_rest: Restore 'kind' property in JSON-mapped objects The datamapper schema has no 'kind' field, instead handling it as a top-level property of the currently unused <xmpp> element and doing this early dispatch on the top level element name. This puts the field back into the output JSON.

This module produces more detailed HTTP logs for Prosodys built-in HTTP
server. The format is similar to that of Apache and go into Prosodys
normal logs at the `info` level.