Client should validate the incoming host value

Convert host:port and URLs passed to client.New() into the proper
values, and return an error if the value is invalid.  Change CLI
to return an error if -master is invalid.  Remove Client.rawRequest
which was not in use, and fix the involved tests. Add NewOrDie

Preserves the behavior of the client to not auth when a non-https
URL is passed (although in the future this should be corrected).

cmd/integration/integration.go

@@ -104,7 +104,7 @@ func startComponents(manifestURL string) (apiServerURL string) {
 		}
 	}
 
-	cl := client.New(apiServer.URL, nil)
+	cl := client.NewOrDie(apiServer.URL, nil)
 	cl.PollPeriod = time.Second * 1
 	cl.Sync = true
 
@@ -301,7 +301,7 @@ func main() {
 	// Wait for the synchronization threads to come up.
 	time.Sleep(time.Second * 10)
 
-	kubeClient := client.New(apiServerURL, nil)
+	kubeClient := client.NewOrDie(apiServerURL, nil)
 
 	// Run tests in parallel
 	testFuncs := []testFunc{