Add BottomNav and other improvements

[louwers]

• Add Bottom Navigation to make the About page less cluttered. Move Brand Assets, Governing Board and Team to separate pages.
• Add MapLibre Tile Specification to the homepage.
• Remove 'additional projects' from the home page. It looks quite cluttered. Added those links to the bottom navigation instead.
• Link to the excellent 'Made with MapLibre' website from @birkskyum from the bottom navigation.
• Make sure the footer shows on the bottom of the page, even on pages that are not very tall.
• Refactor repeated code from the home page in components.

We can bicker about what links should be in the bottom navigation. But it's easy to update later.

[CommanderStorm]

I am fine with the footer, but am a bit sceptical on some of the changes to the about page.
Here are a few of the things that I would like to see changed:

moving the goverment board + team components from the about page to the dedicated pages is something that makes the about page feel rather empty (the dedicated pages also)
I think we should have something there, be it the community map and a link or maybe not even separate them out.

I think the footer has these white lines which the rest of our UI only has sometimes.
I think without the bottm one and the ones below the links it looks more consistent?