The structure of the roadmap isn't meant to support more than 6 tabs, so some changes are necessary to show
the roadmap correctly.
- Grouped the first 2 years 2014-215 on a single tab.
- Added headers for each card
- The last tab is now "Future", and doesn't refer to a specific year, but it's meant to show updates that will be
implemented in the future
- Changed default card from 2019 to 2020
- Deleted roadmap and navigation in root data folder
- Added a language folder (lang) and folders for current langauges with roadmap, navigation, and footer files