Adding @email tags to most of the tests

Reviewed By: rafeca

Differential Revision: D6185623

fbshipit-source-id: 30df83288fe85516d8d5a1617a4fb8fea826ed6f

Libraries/Image/__tests__/assetRelativePathInSnapshot.js

@@ -5,6 +5,8 @@
  * This source code is licensed under the BSD-style license found in the
  * LICENSE file in the root directory of this source tree. An additional grant
  * of patent rights can be found in the PATENTS file in the same directory.
+ *
+ * @emails oncall+react_native
  */
 'use strict';