embedding commands and datatypes onto a page

[Redbot]

Adds macros to embed commands and datatypes into a page, so we don't have to repeat the same information in both index page and sub-page. An example is mq2chatwnd, where information is repeated in the README.md and command pages.

This is a draft pr, with autologin as example. If it looks good, I'll standardize the other core-plugins.

[brainiac]

I like the idea. The screenshots show the old table based datatype though, we are using a newer layout for them. it will still work that way?

[Redbot]

The table based layout is just for embedded content, to save space. If the user clicks through to the datatype's page, they'll see the new layout.

If you want the new layout for embedded content as well, I can nix render_members_table

[Redbot]

Since I was adding other internal plugins, I standardized their naming, dropping the "MQ2" 7f07ccf and updated references to them. e19e820

I added redirects for the index pages in mkdocs.yml, but not each tlo/datatype/command as I thought it would take up too much space.