Adds custom layouts to Layout Builder, which contain options to add css classes and titles to each section.

• Several custom layouts are provided here, which can be further adjusted in the theme.
• Css classes are managed via a vocabulary. There is one vocabulary for general css and another for css to use on titles.
• We use Chosen to make the class selection super easy. That adds tags-style functionality to the simple selector.
• The code massages the Layout Builder block list to change some category names and block titles so they make more sense in Layout Builder.

• Navigate to admin > extend and enable the module.
• The code assumes that vocabularies called classes and title_classes already exist.
• The code assumes a field called field_class is used on these vocabularies to store the actual classes.
• The actual class(es) are stored in a field on the term, which means any descriptive title can be used for the name of the class or class collection.

To include this module in a composer project, add the following to the 'repositories' section of the top level composer.json file:

        "lullabot/custom_layouts": {
            "type": "vcs",
            "url": "https://github.com/lullabot/custom_layouts.git",
            "no-api": true
        }

Then type the following on the command line:

composer require lullabot/custom_layouts