To-do list

[justinpenner]

• [x] Map Hyperglot charsets to Glyphs glyph names instead of checking everything by codepoints, to fix #13
• [x] Implement context menu re: #6 #15
• [x] #17
• [ ] Add unit tests, in preparation for refactoring
• [ ] Refactor codebase into a few modules
• [ ] Automate dependency installs as outlined in #2
• [ ] Add to Plugin Manager