Make all the test pass. Looks like we are HTTP/1.1 compliant.
* bzrlib/transport/http/_urllib2_wrappers.py: Review the debug prints and layered them. (AbstractAuthHandler.auth_required): Clean up the http pipe before issuing the new request after a 401 or 407 auth required error.
* bzrlib/tests/test_http.py: Fix the remaining imports. (BadStatusRequestHandler.parse_request): Simplified. Close connection. (TestInvalidStatusServer.test_http_has, TestInvalidStatusServer.test_http_get): Document pycurl limitations.
* bzrlib/tests/http_utils.py: (RedirectRequestHandler.parse_request, AuthRequestHandler.do_GET): Add a Content-Length header.
* bzrlib/tests/http_server.py: (TestingHTTPRequestHandler.get_multiple_ranges): Close the connection since we didnt specify a Content-Length header.
* bzrlib/tests/http_utils.py: (RedirectRequestHandler.parse_request): Add a Content-Length header.
* bzrlib/tests/http_server.py: (TestingHTTPRequestHandler.handle_one_request): Any socket error close the connection.