I'm not sure this *was* working in Python 3.1, but TravisCI isn't testing it and Tox coughs up an `ImportError: No module named ssl_match_hostname`.  We can look into this more, but supporting 3.1 probably isn't worth it.

Good practice and Python 3.2/3.3 had this to say, `embedly\client.py:152: ResourceWarning: unclosed <socket.socket object, ...>`

…lejson` because we don't support Python 2.5.

Mostly this updates the `Url` model documentation to reflect its more pythonic nature as a true dictionary.
Also update a couple links, don't use `sudo` and fix the RST formatting for a few code blocks.

(This now matches the response decoding already used in `_get()`. It was never noticed because tests didn't cover it.)

This may be overkill but it does increase test coverage and if we develop more fine-grained tests for `_get()` in the future, mock will help.

It doesn't make a ton of changes in truth, but it's a recommended step on the conversion path. It does handle the `urllib` path though!

…the test dependencies

Also test for it, which increases test coverage to 100%.