Streamline global exports for future-proofing and testing purposes

[rdw-software]

Currently, builtins and APIs are simply exported via _G.SomeObject = SomeObject. While that works, it will be very difficult to ever change the behavior across the entire codebase. It's also annoying to test, since messing with the global environment without following a predefined protocol could have plenty of unintended side effects.

To that end, all global exports that exist on purpose, i.e., are not "leaked globals", should follow the following convention:

EXPORT("SomeObject", SomeObject)

where

function _G.export(name, objectToExport)
  -- Sanity checks, etc and print warning if it already exists?
 -- log TRACE("Exported global SomeObject" ?
 -- etc.
  _G[name] = objectToExport
end

This consolidates all modifications of the global environment and provides a streamlined way of doing so that allows mocking (for tests), documenting automatically (scan for export calls), and refactoring/changes in the design (search for export calls in the code).

[rdw-software]

Maybe this should be plugged into the runtime (evo-luvi) itself, as some globals are exported from there also?