Polyfill Safari gesture* & other proprietary events

[Philzen]

This ArcGis online map can be pinch zoomed on iOs, but not on Android, even not on Version 4.

This leads to the conclusion there must be fundamentally different events being triggered by iOS and listened to by the ArcGis map, which aren't triggered in iOs (most probably the gesture* events, but need to check) .

It might be a nice optional feature to polyfill whatever difference there is to iOs, though one might argue should be a project or class of its own.