Do not assume images would be placed in `/assets/images/`

In order to add an image to a post, just use the following syntax:

{% include image image_path="/full/path/to/MyPostImage.png" caption="The optional image caption" %}

or

{% include image image_path="https://example.com/images/MyPostImage.png" caption="The optional image caption" alt="The optional alt text" %}

Replace base_path with `absolute_url` filter

Update image

add image helper for easier image insertion in posts

Add pre-release theme gem link

Merge branch 'release/3.4.8'

Update CHANGELOG.md and bump version to 3.4.8

Update gems: `github-pages` (96), `jekyll-mentions` (1.2.0)

Merge branch 'feature/portuguese-update' into develop

Re-add Brazilian Portuguese localized strings

Merge branch 'master' of https://github.com/fa-ribeiro/minimal-mistakes into feature/portuguese-update

includes: Enhance Twitter share link (#538)

* Include the page title before the URL
* If twitter.username is set, pass the `via` paramter for attribution

Fixed Last.fm URL (#540)

lastfm.com/user... results in a server error, last.fm/user... is the correct URL.

update Portuguese translation

Merge branch 'feature/large-screen-font-size' into develop

Merge branch 'master' of https://github.com/jhabdas/minimal-mistakes into feature/large-screen-font-size

Typography for larger viewports. Closes #533

Remove empty maintenance listing

Remove empty maintenance listing

Merge branch 'release/3.4.7' into develop