Add save/load for client config

cmd/client/actions/actions.go

@@ -56,6 +56,10 @@ func ActionLogin(c *cli.Context) error {
 		errmsg := fmt.Sprintf("Error logging in: %s", err)
 		return cli.Exit(errmsg, 1)
 	}
+	if err := clnt.WriteConfig(); err != nil {
+		errMsg := fmt.Sprintf("Failed to write config: %s", err)
+		return cli.Exit(errMsg, 1)
+	}
 	// TODO: Store this somewhere, so we don't need to log in each time
 	fmt.Println("Successfully logged in.")