Add `id` to page title

Convert EOL sequence to LF

Upgrade Font Awesome to version 5 (#1446)

Upgrade Font Awesome to version 5 (SVG with JavaScript)

Close #1396

Merge branch 'master' of https://github.com/mmistakes/minimal-mistakes

Remove comments in dev environment (#1363)

Merge branch 'master' of https://github.com/mmistakes/minimal-mistakes

# Conflicts:
#	docs/_docs/18-history.md

Toggle table of contents via front matter (#1310)

* Add jekyll-toc include
* Reduce whitespace generated by comments
* Add table of contents include to `single` layout
* Replace `toc` include with jekyll-toc enabled YAML Front Matter
* Update README
* Update table of contents documentation
  - Revise `toc` helper include to mention that it will be deprecated in the next major version.
  - Add documentation to `single` layout explaining how to enable table of contents on those pages.
* Update CHANGELOG and history
* Update LICENSE

Close #1222 

Color "skins" (#1242)

* Add YIQ Color Contrast mixin
* Remove text underline from `.btn` links
* Move YIQ variables
* Simplify button classes using YIQ color contrast mixin
  - DRY up button CSS using Sass list and YIQ color contrast mixin.
  - Move `color` and `background-color` to new `btn--primary` class instead of assinging on the default class. Removes the need to override them.
* Add `.btn--primary` to buttons that just had `.btn`
* Apply changes to `/docs`
* Add `.btn--primary` class
* Update CHANGELOG and history
* Add sample form
* Abstract colors away into Sass variables for easier themeing
* Add "dark" skin
* Replace hardcoded color with SCSS variable
* Invert Font Awesome icons' colors in author sidebar and footer
* Add Sass changes to `/docs`
* Use primary button type instead of inverse
* Add missing `!default` on `$muted-text-color`
* Add `contrast` and `sunrise` skin colors
* Add `dirt` skin color
* Add `air` skin color option
* Add `mint` skin color
* Add `btn--primary` class to Submit Comment button
* Set skin to `default`
* Document skin color options
* Add note about skin SCSS import

Close #1208 

Show 4 latest posts when `site.related_posts` is `nil`

`site.related_posts` should return an array of latest posts when no related ones are found due to `lsi` being disabled (GitHub Page's doesn't support it).

This works around that bug by showing the 4 latest posts to populate the "You May Also Enjoy" module when enabled with `related: true`.

Fixes #554
Related: #978 #1022

Replace modified with last_modified_at (#930)

Fixes #929

Merge branch 'release/4.3.1'

Remove buggy conditional around related posts header (#901)

This removes a buggy conditional that checks if `related_label` is
available in translations before displaying the header for related
posts but this header already handle missing translation by using a
default string.

With this fix the header is displayed even if the translation for this
label isn't available.

Fix #900

Merge branch 'release/4.2.0'

Add page hero video for vimeo/youtube using embedresponsively.com code (#788)

Merge branch 'release/4.0.4'

Conflicts:
	README.md

Merge branch 'feature/theme-gem' into develop

Replace base_path with `absolute_url` filter where possible

Merge branch 'release/3.4.4'

Merge branch 'feature/fix-page-hero-liquid-warning' into develop

Merge branch 'hotfix' of https://github.com/vwchu/minimal-mistakes into feature/fix-page-hero-liquid-warning