Add support for other languages in the frontend

[willemarcel]

I'm submitting a feature request

Brief Description

Make the frontend localized and translated in many languages.

What is the motivation / use case for this feature?

Makes it easy to use for all OSM community.

[eduardoaddad]

we can create as implicit somewhere on a website or make a translation directory

[danieldegroot2]

Ref #728

See also openstreetmap/openstreetmap-website#5769 (scroll down a bit)
While it might not become as complicated, issues with inacurrate timestamp translation and timezones may still arise.