New release where we use our own definitions of (IMHO) completeness and correctness. Bring in more categories of non-printing (i.e. zero width) based on Go stdlib Unicode categories.

• Drop the attempts at compatibility with go-runewidth by @clipperhouse in https://github.com/clipperhouse/displaywidth/pull/3
• Trie cleanup by @clipperhouse in https://github.com/clipperhouse/displaywidth/pull/4

Full Changelog: https://github.com/clipperhouse/displaywidth/compare/v0.2.0...v0.3.0