Fix missing import
Add use of urllib for HTTP functionality
Add slightly friendlier method for HTTP views

Add the `_http_view` method on `Connection` for the common case of
querying normal views on a bucket (libcouchbase LCB_HTTP_TYPE_VIEW)
without all the trouble of manually marshaling and unmarshaling
arguments, dealing with the libcouchbase HTTP request type, and so on.
Flesh out examples of using _http_view
Add tests for _http_view method