Merge pull request #5 from willnorris/appengine

fixes for app engine, JRD marshalling, and draft-14
add conf for Travis CI
Replace the plain text README by a markdown version.
refactor api for working with Resources

WebFinger resources can simply be treated as URLs with some extra logic
surrounding extracting the host for acct and mailto URLs.  This now
supports all types of URLs, not just email addresses, however if an
email-like identifier is provided, it is treated as an acct URI.  Full
tests for the Resource type have been added as well.

!! This is a breaking change.
simplify api for querying webfingers

Combine GetJRD and GetJRDPart into a single function, now simply named
Lookup.  This takes a string as input, so callers don't need to parse
the resource identifier beforehand.  Also provide a default client, so
now you can do a webfinger lookup with one call:
    webfinger.Lookup("will@willnorris.com", nil)

This includes complete test coverage for the new Lookup methods.

!!! This is a breaking change
add option to allow http lookups and fix AppEngine

By default, all lookups must be over https (per the WebFinger spec).
Add flag on Client to allow for http.  Also fix error checking for
AppEngine.
add webfist support