Add a way to safely embed links to relevant resources within a Rule

More broadly, this is a strategy for integrating the layers of community life and embedding pointers to them in the Rule. Two approaches:

Structured links associated with each section, e.g., Modules on Democratic Mediums, Contributor Covenant, Loomio page, Open Collective page
Arbitrary links within text

Could be:

Have a link icon with each question
When user presses icon, two fields come up: Resource Name and URL, and an "Add" button
This adds a link under the text of that field
Use a captcha?
Markdown support

Arbitrary links run risk of spam. And currently we strip all HTML tags from text.

#8 Add a way to safely embed links to relevant resources within a Rule