Redirect old links in docs to new ones in VuePress

[chrisvfritz]

Since a lot of courses, books, blog posts, etc still link to pages in the non-VuePress docs I'm thinking some redirects should be set up. Unfortunately, I don't have a complete list of links, but here's one.

[posva]

Yeah, same as #2214
I wanted to make the redirect but saw Evan added it then removed it, so waiting for an answer 😓