Add a swipe command

[marlowpayne]

We really need a swipe command to test gestures on page elements (swipe through carousels, etc).

Potential arguments could include:

• Origin point (be it specified through CSS selector or pixel position)
• Direction to swipe
• How many pixels to swipe before touch release
• A perpendicular variation factor to include in the swipe gesture (No one can swipe perfectly straight. This could be a pixel factor that 'fudges' the swipe to make it realistic)

[qa-derrick]

possible JSON wire protocol commands to develop off of include:
https://code.google.com/p/selenium/wiki/JsonWireProtocol#POST_session/:sessionId/touch/move
https://code.google.com/p/selenium/wiki/JsonWireProtocol#POST_session/:sessionId/touch/scroll
https://code.google.com/p/selenium/wiki/JsonWireProtocol#POST_session/:sessionId/touch/flick

[qa-derrick]

The swipe event has still not been included in the protocol.

[industral]

industral/nightwatch@master...touch