Port from Obj-C to Cordova/Xamarin/Phonegap

[vineetsk1]

(Would allow for Android support)

[luxaritas]

As referenced in #1, we're looking to use HTML-Chat as the basis for the chat portion of this app (as the idea is to expand beyond chat) going forward, tentatively starting with v4. This will allow for a unified codebase (chat will remain consistent across web and mobile, plus less code to deal with), and quickly port to multiple mobile platforms.

I'm tempted to say stick with Cordova and probably add Ionic for native UI components. I'm guessing we don't particularly want Adobe's services, which is the main benefit of PhoneGap.