Update retext, nlcst-to-textom, retext-emoji
Fix incorrect executive rights on `test.js`, `example/index.js`
Refactor npm script targets in `package.json`
Refactor `example/index.js` for changes in retext
Add flat badges to `Readme.md`
Refactor `Readme.md`
Update changelog for 0.0.4
0.0.4