Support for intercom.io, fixes inconsistent test fails.

Hey there,

This is Steven, the guy who also added gaug.es support.  This PR adds support for intercom.io, as well as fixing up some annoying inconsistent fails because of `json`'s inconsistent dict rendering order.

Believe everything's here (tests, docs, etc), if not, ping and I'll add it quickly!

Thanks again for the great lib,
-Steven