Cleanup old stream stuff

/cc @wheresrhys @kaelig @laurent-muchacho @commuterjoy 

- Remove anything stream related from Grumman to avoid confusion!
- Rename article-card classes to article so it doesn't clash with cards
- Bring in template copying from dobi
This article-card__link should evenually be removed, but needs a change to all the save/recommend buttons which are explicitly looking here for a headline, so will do separately