[misc] add usecase for gamepad

Impacted Suites: webapi-usecase-w3c-tests
Impacted TCs num: New 0, Update 1, Delete 0
Unit test Platform: Andriod
Andriod test result summary: Pass 0, Fail 1, Blocked 0

Comments:
1. Because gamepad feature moved to V8, so change the status to designed.
2. Tizen is not support this API.
Merge pull request #244 from JianfengXu/xujf/misc/gamepad

[misc] add sample app for gamepad