[TIMOB-27632] API: Review uncaughtException event property parity

Raised in this PR discussion: https://github.com/appcelerator/titanium_mobile/pull/11352#discussion_r349168870 We should at least get the deprecations in for 9.0.0. Android has: - javascriptStack, which is a String and contains the javascript stack trace - javaStack, which is a String and contains the Java stack trace - lineOffset, which is a Number and basically is the column iOS has: - column which looks equivalent to Android's lineOffset - stack, which is a String and contains the javascript stack trace - nativeStack, which is a String and contains the Obj-c stack trace There's a property documented as {{backtrace} which I don't think any platform provides. We should standardize on stack for the JS stack trace, mark backtrace removed (when?), mark javascriptStack deprecated. Same idea for standardizing on nativeStack over javaStack (probably deprecate javaStack to be removed in the future like SDK 10?)