Update dependencies

- Update eslint, retext, retext-visit, jsdom, mocha;
- Remove retext from peer-dependencies.
Refactor spec

Includes a rewrite for retext ^0.2.0-rc.1
Remove testling
Update copyright in docs
Fix property order in component.json, package.json
Add bower.json
Update Installation in docs

- Add Bower as an installation method;
- Rename Component.js > Component;
- Fix casing of NPM > npm.
Update .gitignore, .npmignore
Remove `npm update` from travis
Add npm deployment to travis
Refactor API
Update Readme.md
Update retext-visit in bower.json, component.json
Update changelog for 0.1.3
0.1.3