WIP: Add links to rebranded code examples

[domoscargin]

What

Adding a rebrand: true frontmatter property to any code example will (during build):

• Duplicate that file before running Metalsmith/in-place, renaming it from index.njk to branded.njk
• Change the layout property for that file to point at the branded/ subdirectory, to take advantage of {% set govukRebrand = true %} (potentially this could be automated as well, so we don't need to manually duplicate/maintain the layout files either)
• Run a custom jsTransformer on the nunjucks which inserts rebrand: true into govukHeader and govukFooter macro calls
• Saves the file to [type]/[title]/[example]/branded/index.html (eg: components/header/default/branded/index.html)

To do

• In the first instance, hopefully we'll have access to a Nunjucks global in order to make this a lot simpler, but in case that doesn't happen for a while, we can work with this.
• Add the property to each relevant file
• Create/update the brand tag/note macro which will link out to these examples
• Potentially automate the layout transform as well
• Document and test

Future

It should be relatively easy to swap all the "branded", "rebrand" naming for something like "legacy" or whatever we want to call our current styles when we eventually default to the rebrand styles.

[netlify]

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