Adding hidden-print to a few places
Print the TOC; a bit condensed
Use download-btn on all download buttons
Forgot the hero button
Tidy up the README
Fixing mixin article example
Clarify Adwords for video
Added marketing tool to Who Uses Dart
Merge pull request #960 from srawlins/issue-943-download-btns

Use download-btn on all download buttons
Remove 'Function'
Merge pull request #962 from srawlins/issue-854-mixins-article

Fixing mixin article example
Merge pull request #959 from srawlins/issue-339-print-fixes

Adding hidden-print to a few places
Update as per review comments
Merge pull request #961 from srawlins/tidy-readmy

Tidy up the README
Merge branch 'master' into issue-910-markdown-notes

* master:
  Update as per review comments
  Remove 'Function'
  Added marketing tool to Who Uses Dart
  Clarify Adwords for video
  Fixing mixin article example
  Tidy up the README
  Forgot the hero button
  Use download-btn on all download buttons
  Print the TOC; a bit condensed
  Adding hidden-print to a few places
Tweak text