Add ability to use JSON/JSONC file instead of XML for tiapp.xml

[brentonhouse]

Currently, Titanium uses XML (with tiapp.xml) for configuring a mobile application. Moving to JSONC (JSON with comments) like Microsoft has done with VSCode configuration and settings files (https://github.com/microsoft/node-jsonc-parser) would allow far more extensibility when it comes to merging configurations based on user, platform (iOS, Android), or type of build ( Dev, QA, Staging, Production ).