Create a 2020 website version

[alster-wasser]

(as soon as we have official confirmation)

[emrox]

• create repository: https://github.com/rubyunconfeu/2020-website
• configure DNSimple to alias 2020.rubunconf.eu towards the GitHub Page
• HTTPS setup for the page
• create placeholder page
• change forward for rubunconf.eu from 2019.rubunconf.eu to 2020.rubunconf.eu

[stex]

Not sure if the "help wanted" label is still in effect, if yes, I could help here as well if needed.

[emrox]

@stex good point, I removed the label for now

[emrox]

changed content of my first comment here to document initial progress

[emrox]

I've changed the title to reduce the scope. We should add details when we have them confirmed and create separate issues/MRs for the different parts