Tracking: Maintenance and modernization

[jhenahan]

I've been maintaining this tool quite poorly, mainly because my total utility for tag files has been pretty supplanted by HLS of late, but I'm coming back around to see the use. To that end, I intend to set aside some time each week to at least think about some of the existing open issues and put some focused effort into thinking about and refactoring the code that's here today. PRs and issues are of course still welcome, but I expect to be focused on refactoring and updating for some time. PRs will take priority over issues until things are in a happier place. Thank you for your patience. :)

Related:

• #80