imp: Add templates to rn package (facebook#22952)

Summary:
Changelog:
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[General] [added] - Add `templates` to `react-native` package.

We need a `template` to initialize new RN project from `react-native-cli`. We are planning to remove `templates` from `cli` to be always synced with chosen rn version. Issue for that in `react-native-cli` is here: react-native-community/cli#39 .
cc grabbou cpojer
Pull Request resolved: facebook#22952

Differential Revision: D13644364

Pulled By: hramos

fbshipit-source-id: d5d7a820ffacb342e1e97d83739987678ff511e9

package.json

@@ -128,7 +128,8 @@
     "ReactAndroid",
     "ReactCommon",
     "README.md",
-    "third-party-podspecs"
+    "third-party-podspecs",
+    "template"
   ],
   "scripts": {
     "start": "node cli.js start",