Remove createReactClass from SwipeableRow (facebook#21876)

Summary:
Related to facebook#21581

Remove createReactClass from SwipeableRow.

- All flow tests succeed.
-RNTester > SwipeableFlatList, scroll, swipe left, swipe right
-RNTester > SwipeableListView, scroll, swipe left, swipe right

[GENERAL] [ENHANCEMENT] [SwipeableRow.js] - rm createReactClass
Pull Request resolved: facebook#21876

Reviewed By: TheSavior

Differential Revision: D12828034

Pulled By: RSNara

fbshipit-source-id: df02ed14e72bf6b0ad3cff33076a6f40870266a8