Adding bookmarklet version of Pesticide.

* Added `minify-js` task to compile the bookmarklet script to a minified version.
* Added minified bookmarklet script.
* Added `gulp-concat` and `gulp-uglify` as Node dependencies.
Merge branch 'feature/bookmarklet' of github.com:rafaelrinaldi/pesticide into rafaelrinaldi-feature/bookmarklet

* 'feature/bookmarklet' of github.com:rafaelrinaldi/pesticide:
  Adding bookmarklet version of Pesticide.