Better rules/data

From https://github.com/snowplow/referer-parser/blob/master/ruby/data/referers.json

Some wins:
 - A whole lot more social site rules, this was how I originally found the data.
 - A set of email site rules, so now we have an `email` referrer type.
 - Faster referrer parsing with constant time domain-mapped rule lookups.

A couple possible issues:
 - I had to manually add the search engine rule for domain `ca.search.yahoo.com`, because it wasn't there, so what else is missing?
 - The search engine discovery isn't exactly the same in this implementation as before, where before we matched based on domain parts, now we just look for whole domain, is this a problem?

@mkobetic @boourns @fw42 @Sirupsen