Remove support for autolinks (<..>)

[srid]

Note: this applies to use of autolinks to link to other notes (eg: <foo-bar> or <z:zettels?...>)

These are already deprecated; let's remove them to keep the code simple. Last discussed at #437 (comment)

• Stop accepting short-links (eg: <foo-bar>)
• Lift suppression of raw HTML parsing by commonmark parser

[srid]

Here's a script to migrate from old autolink format:

https://gist.github.com/srid/fb202ad906b32cf00803f4332d4c3d59#file-neuron-migrate-wikilinks-sh

Read the comments carefully before running this script in your Zettelkasten.