Persist Quill alignment options

[salomoneb]

Description

Quill has an align option. Specifying this creates a button which allows you to choose a text alignment.

I added this to my inline form input like so:

overrideHeadline:
  _label: Headline
  _publish: articleHeadline
  _placeholder:
    height: 40px
  _has:
    input: inline
    buttons:
      - italic
      - strike
      # https://github.com/quilljs/quill/issues/1969#issuecomment-389697111
      - align: ["", "center", "right"]

I can align the text through the editor, but the alignment doesn't persist on save. Demo:

alignment.mov

There's a ql-align-* class that gets added to the Quill wrapper class while editing, but which gets stripped on save in inputs/wysiwyg-sanitize.js.

@james-owen and I talked over Slack about adding a transformTags function to wysiwyg-sanitize.js that would look for the special Quill alignment classes and add the alignment preferences as inline styles to the parent text element:

grab all paragraphs, grab their styles, if they match our list add them to parent element, strip p tags.

Expected Behavior

Kiln should save my alignment preference.