Created a Vimeo Provider for AllAuth

Using the LinkedIn provider as a base, I created a Vimeo provider based on https://developer.vimeo.com/apis/advanced and using https://developer.vimeo.com/apis/advanced/methods/vimeo.people.getInfo to retrieve user information.

You'll notice I had to modify (rather heavily) VimeoAPI.to_dict xml parsing to support node attributes which Vimeo used heavily for holding specific data (like user id, for example).  If I were keeping this custom, I probably would've used their JSON format as it was much more legible, but I wanted to stick to XML to keep consistency with your other providers.

Everything else is fairly standard - Vimeo doesn't provide a first name or last name so I used a couple of string split methods on the display_name node.

Vimeo doesn't appear to support SCOPE (like Facebook or other providers do) and instead takes an x_auth_permission parameter set to read, write, or delete.  I only needed the read permission, so I didn't set up the provider to handle the other two.