I noticed most asset links use relative URLs, except for a few. This commit remedies this inconsistency.
OpenGraph embeds were not changed, because in my experience, some embed scrapers require absolute URLs.

Motivation: The site I use has an onion and a clearnet version, and currently, visiting the onion loads fonts, styles, and the favicon
over the clearnet.

This adds beginning email subscription functionality, with only MySQL support,
Mailgun support, and incomplete support for private instances. It includes
database changes, so run:

    writefreely db migrate

to use this feature.

Ref T856

Ref T770

This adds a configuration option to the [app] section: open_deletion. When
true, users can delete their account on their own.

Ref T319

This requires admins to generate a new encryption key with:
  writefreely keys generate

Ref T319

This mimics the admin UI for deleting a user account.

Ref T319

Ref T319

Ref T401

Ace doesn't work well with touchscreen devices, so instead we fall back to a
plain textarea.

From the writeas org on GitHub.

This fixes an issue with Safari not allowing users to select *.md files.

Closes #334

This fixes #280 in all editors, continuing work from #435.

This continues work by @cjeller1592 in #435.

Closes T492

Mostly copied the logic for pagination from non tag collection

This makes it so that if a post is updated, it will retain the language metadata rather than revert back.

This automatically lowercases language names used in code blocks when finding highlighting scripts for them, since highlightJS defines all languages with lowercase names.

Some WriteFreely instances are completely private, and thus have no need for public-
oriented features like Web Monetization. Like federation, this gives admins control
over whether or not the feature is enabled for users.

Ref T773

Ref T773

Closes T708

The header shouldn't include the `dated` property, since we don't display a date
on pinned posts. This fixes that.

This uses the main navigation bar for the Customize and Stats pages, instead of the collection-navigation bar used for multi-user / multi-collection instances.

This makes it easier to navigate between different blog sections: Customize, Stats, View.

This includes the platform mark with each login button and uses
brand colors. It also uses the same style on the Account Settings
page. And it wraps buttons on login / signup pages.

This moves fields into the `OAuthButtons` struct and puts the buttons into templates/includes/oauth.tmpl.

This supports a new `monetization_pointer` collection attribute.
When present, we include the `monetization` meta tag on all
collection pages.

This adds a "load more" button to the bottom of the draft posts page,
which calls /api/me/posts with new parameters and the current page
number. It then populates the page accordingly.

Ref T696 - load anon. posts with ?anonymous=1&page=1
Ref T401 - completes UI for post loading

This enables users to add a signature to all blog posts, and update it from a single location.

Requires database migration with: writefreely db migrate

Closes T582

Fixes #41

Add generic Oauth allow_logout option