Handle redirects / old links

[Manuel Spigolon]

We must support all the old website links from https://fastify.io/

After merging #44 it seems that:

• https://www.fastify.io/docs/latest/ works as expected
• https://www.fastify.io/docs/master/ is being redirected to latest. We may thing if we want the canary link as docusaurus does: https://docusaurus.io/docs/next. I think the support the redirect from /master is good, I would drop this wording as fastify did in its main branch
• https://www.fastify.io/docs/v4.11.x/ supported
• https://www.fastify.io/docs/v3.4.x/ et similar, should be redirected to v3.29.x
• https://www.fastify.io/docs/v2.9.x/ et similar, should be redirected to v2.15.x
• https://www.fastify.io/docs/v1.3.x/ et similar, should be redirected to v1.14.x
• Other page links

💡 An interesting thing to implement: AFAIK Docusaurus does not support one documentation version with multiple labels (eg: create one /versioned_docs/v2.x that creates the routes /v2.15.x, /2.14.x etc...). It would be awesome to build a plugin that does this trick

[Manuel Spigolon]

This should be done, it requires to test it a bit more

[Manuel Spigolon]

Works for me