Recieve webmentions - Store comments, likes, etc.

[TomboFry]

If people comment, like, or repost one of your entries, this should be reflected on the entry page. This is likely going to require another database table (or two) to store them.

• Person table for storing unique individuals interacting.
• Interaction table, referring to a specific person and post.

However, because I value data collection and privacy, a disclaimer should be displayed somewhere on the page stating that their data can be permanently removed from the site by emailing the site owner. Hooray for GDPR!

• [x] Create tables
• [x] Display webmentions
• [x] Webmention endpoint
  • [x] Determine entry type on source URL
  • [x] Determine post content on source URL
  • [x] Determine published date on source URL
  • [x] Determine author card details (image, name, URL)
  • [x] Store interaction in database
  • [x] Retrieve person from database if they already exist (instead of inserting)
  • [x] Update person cache's image URL and name if they already exist
  • [x] Support updating existing webmentions (which includes preventing duplicate interactions)
  • [x] Support deleting existing webmentions (if, upon updating, the source URL return 410 Gone)
  • [x] Limit fetching source contents to 5 seconds or 1MB of data
  • (optional) Provide CSRF token on a post's webmention URL and validate it before accepting. See Cross-Site Request Forgery.

[TomboFry]

Webmentions processed and stored as of 4872db8, but further processing will need to be done to prevent duplicate webmentions from being stored, as well as determining what type of webmention is being added (eg. reply, like, repost, bookmark, etc)

[TomboFry]

Webmentions are now updated (no more duplicates) and deleted as of 73d2765. Coming up next: post type detection!

[TomboFry]

Post type detection as of 095cc52! Just going to tighten security a little and call this done.