Add docs to Gestures module
Add docs to Gestures module

Signed-off-by: Tobias Roikjer <cbf4de1dc17b657ebb10265e5e61c5cf21b59123@xamarin.com>

tejasv02/calabash,tejasv02/calabash,calabash/calabash,tejasv02/calabash,calabash/calabash,calabash/calabash