* Split website in 4:
- build
- run node
- learn
- research
* only show pages of section in sidebar
* home button on each sidebar
* index.md for homepages
* Add video tutorials
* delete old getting-started
* rename to "Waku node"
* fix nwaku compose
* add to dict
* script revert research changes
* fix broken links
* move research index content
* move research folder under learn
* move research folder under learn: side bar and buttons
* remove pointless links
