Display the client_uri

[TimothyBJacobs]

From the spec:

URL string of a web page providing information about the client.
If present, the server SHOULD display this URL to the end-user in
a clickable fashion. It is RECOMMENDED that clients always send
this field. The value of this field MUST point to a valid web
page.

We should add the client_uri to the connection page. I think we should probably also require that the client_uri is sent. We'd also need to verify that the redirect_uris match the client_uri.

[TimothyBJacobs]

Added to the connect page, as well as the admin interface. Definitely needs copy and UI eyes. I think this will also be benefited by #18 where we can say whether this is "verified" to some degree or not.