Summary: Adds UI to the select the plugin to export. It lists the plugins which has currently some data in the redux store and it also lists those plugins which has implemented `exportPersistedState` function, as it might happen that the redux store may not have the data for a plugin but it will still export the data by calling `exportPersistedState`, which will ping the mobile client to get the data at point while we export the flipper trace.
Reviewed By: jknoxville
Differential Revision: D16468408
fbshipit-source-id: 452a7caf7199dd2b8df330bbb10d0a90008e92ec
e7198040ea