Introduce Metro device and plugin

Summary: Introduced Metro device and the possibility to directly connect to running Metro instances

Reviewed By: jknoxville

Differential Revision: D19445623

fbshipit-source-id: 31978d966a56007c48f795076d6651e23de0e38d

src/dispatcher/index.tsx

@@ -8,6 +8,7 @@
  */
 
 import androidDevice from './androidDevice';
+import metroDevice from './metroDevice';
 import iOSDevice from './iOSDevice';
 import desktopDevice from './desktopDevice';
 import application from './application';
@@ -28,6 +29,7 @@ export default function(store: Store, logger: Logger): () => Promise<void> {
     application,
     store.getState().settingsState.enableAndroid ? androidDevice : null,
     iOSDevice,
+    metroDevice,
     desktopDevice,
     tracking,
     server,