Custom URL scheme with launch URL support.

[florisdipt]

Why/User Benefit/User Problem

We would like the user to be able to launch this application with a link and a url.
Currently we would have to guide them through copying the link to our application they want to view, making them download the application from the App store and finally pasting the link into the browser.
This can be quite confusing for some users.
Having the ability to launch the app with a url would save one of these steps thus being less prone to user error.

Acceptance Criteria (how do I know when I’m done?)

Implemented URL scheme that accepts a url to be passed to it.
https://developer.apple.com/documentation/xcode/defining-a-custom-url-scheme-for-your-app

For example being able to click
edu.cmu.wiselab.XR-Browser://example.com/slug/1/slug/2 on a iPhone and having it launch XRBrowser with example.com loading

Not included

[florisdipt]

Also thank you for forking this since it seems Mozilla has halted development on the XRViewer app.