Custom URL Scheme Support

Here is the official guide for pulling this off:

http://developer.apple.com/library/ios/#DOCUMENTATION/iPhone/Conceptual/iPhoneOSProgrammingGuide/AdvancedAppTricks/AdvancedAppTricks.html#//apple_ref/doc/uid/TP40007072-CH7-SW50

With this, we can have links like scribbeo://app.scribbeo.com/... and have them trigger Scribbeo launch.

This is in the TDS spec and must be done by Dec 1st.
