Fixes for help content found by Levert (issue #200); fixed linking between topics.
Restored fixed height to Competition-Tile images
Merge branch 'master' of github.com:codalab/codalab
Merge pull request #201 from willum070/docs

Thanks @willum070!
Minor Help page tweaks. Fixes #200
Fixing merge conflicts. Fixes #200
Fix logic in is_active
Merge branch 'master' of github.com:codalab/codalab
Merge branch 'master' into beaudev