Fixes grammar issue in README.md
Merge pull request #278 from ktagliabue/master

Fixes small grammar issue in README file.
GPL version clarification
select a step more precisely.
Merge pull request #288 from jenil27/master

auto-resizing doesn't work when `active` class is used anythere on a page
added impress.js challenge banner
Typo

:)
Merge pull request #300 from DronRathore/readme.md---typo

Typo in README
end of challenge
Update impress.js

Fixed typo from "how thing work" to "how things work"
Merge pull request #316 from bijanbwb/patch-1

Fixed typo from "how thing work" to "how things work"