Use express 4
prepare guides
add Class and Drag
Merge pull request #98 from SergioCrisostomo/fix-guides

Prepare for guides
Merge pull request #96 from SergioCrisostomo/express4

Use express 4
polish & fixes after ML feedback

- removed dropdown
- fixed padding
- fixed `:active` background-color around logo
- fixed logo width behaviour in Win Chrome
- aligned search box