Create hub page and link from all footers

[cjyabraham]

Create new hub page on CNCF.io that lists all subsites in the CNCF web ecosystem. Link to it from all footers to promote discoverability among all sites.

Footer design assets needed:

• [x] Desktop footer on cncf.io site
• [x] Mobile footer on cncf.io site
• [x] Desktop footer on subsite like glossary
• [x] Mobile footer on subsite like glossary; note we need to accommodate the lang selector here

Hub design should show off the following sites, grouped by category (all TAG sites together, for example):

• Main cncf.io site
• Landscape
• Community
• Jobs
• Store
• Contribute
• Glossary
• AppDelivery
• MaturityModel
• Sustainability

Each site could have its logo, a short description, and a link to its repo (encouraging contributions or issues).

• [x] We need both a desktop and mobile design for this hub page.

[cjyabraham]

Footer design attached:

[GarethAcidWorks]

Hi all, i have spent some time trying to figure out a neat and tidy solution for handling our hub links. We need multtiple links of course and also the option to scale and navigate as the site landscape grows.

I have made a short video to support the recommendation below:

Desktop - 'Micro arrows that cause minimal distraction from the page flow. Mobile - Swipe to see more

[GarethAcidWorks]

Adding latest designs

[cjyabraham]

Hub pages is live: https://www.cncf.io/all-cncf/ Footer implementation split into separate issue.