Investigate overall effectiveness of global.json file for locking SDK version in pairing sessions

[rjrjensen]

Erik brought up re-adding the global.json just as a precaution and I want to make sure that there won't be an issue with leaving it out. I always aim for fewest files, lines per file, etc., but if global.json saves us a headache later, I'll cave and add it back.

Message

Overall LGTM.

Minor nit on line endings, typically there's a \n at the end of every file. This symbol means the final newline is missing

Also curious about your thoughts on the removal of the global.json file? Typically its better to pin dependencies.

Originally posted by @UnstoppableMango in #350 (review)