Adding composer.json

This allows luigi to be pulled in using composer
Removing trailing comma in composer.json
Updating composer.json and adding licence

Luigi is now licenced under GPL v2.

Also added composer.json so it can be submitted to packagist. This
resolves #5
Adding bower.json file for installation through there
Merge branch 'develop'
Update default animal breakpoints
Add animation, keyframe and unselectable to readme
Add links to readme index
Update readme and bower.json for v1.4.0
Change version position in readme
Add attribute in 'transition-transform' mixin

- Fixes #10