Fix assorted tslint violations

[c-w]

No functional change, just letting VSCode fixup some files and extracting some methods to prevent variable shadowing.

This PR goes a long way towards resolving #13: we now only have 4 errors left, all of which are programming errors instead of style errors:

[morsh]

@c-w - This is a blessed undertaking!!
I'll merge this first thing next week (Sunday) and make the appropriate test.