Add list-devices option to list the available devices.

Summary: This diff adds an option of `--list-devices` which will list the currently active devices on the machine. It will be later used to select a device by passing an `id` as an argument.

Reviewed By: danielbuechele

Differential Revision: D15524250

fbshipit-source-id: 7a79ceb1e431a25adcb4e05bc0cb68407c527806

src/reducers/application.js

@@ -30,6 +30,10 @@ export type LauncherMsg = {
   message: string,
   severity: 'warning' | 'error',
 };
+export type ServerPorts = {
+  insecure: number,
+  secure: number,
+};
 
 export type State = {
   leftSidebarVisible: boolean,
@@ -39,10 +43,7 @@ export type State = {
   activeSheet: ActiveSheet,
   exportFile: ?string,
   sessionId: ?string,
-  serverPorts: {
-    insecure: number,
-    secure: number,
-  },
+  serverPorts: ServerPorts,
   downloadingImportData: boolean,
   launcherMsg: LauncherMsg,
 };