Add custom classes to Bolt wysiwyg editor

wysiwyg:
    images: false            # Allow users to insert images in the content.
    anchor: false            # Adds a button to create internal anchors to link to.
    tables: true            # Adds a button to insert and modify tables in the content.
    fontcolor: false         # Allow users to mess around with font coloring.
    align: false             # Adds buttons for 'align left', 'align right', etc.
    subsuper: false          # Adds buttons for subscript and superscript, using `<sub>` and `<sup>`.
    embed: false             # Allows the user to insert embedded video's from Youtube, Vimeo, etc.
    underline: false         # Adds a button to underline text, using the `<u>`-tag.
    ruler: false             # Adds a button to add a horizontal ruler, using the `<hr>`-tag.
    strike: false            # Adds a button to add stikethrough, using the `<s>`-tag.
    blockquote: false        # Allows the user to insert blockquotes using the `<blockquote>`-tag.
    codesnippet: false       # Allows the user to insert code snippets using `<pre><code>`-tags.
    specialchar: false       # Adds a button to insert special chars like '€' or '™'.
    ck:
        autoParagraph: true  # If set to 'true', any pasted content is wrapped in `<p>`-tags for multiple line-breaks
        disableNativeSpellChecker: true # If set to 'true' it will stop browsers from underlining spelling mistakes
        allowNbsp: false     # If set to 'false', the editor will strip out `&nbsp;` characters. If set to 'true', it will allow them. ¯\_(ツ)_/¯

        # -- mysite.nl -------------------------------------------------------------------------- #
        # default : "p;h1;h2;h3;h4;h5;h6;pre;address;div;info;warning;error;success"
        # removed : h1, pre, address, div
        # added   : info, warning, error, success
        format_tags: "p;h2;h3;h4;info;attention;tip;warning;follow_up"
        format_info:
            name: "Info"
            element: "p"
            attributes:
                class: 'ui-info info'
        format_attention:
            name: "Attention"
            element: "p"
            attributes:
                class: 'ui-info attention'
        format_tip:
            name: "Tip"
            element: "p"
            attributes:
                class: 'ui-info tip'
        format_warning:
            name: "Warning"
            element: "p"
            attributes:
                class: 'ui-info warning'
        format_follow_up:
            name: "Follow up"
            element: "p"
            attributes:
                class: 'follow-up'