In DM-11513 (and RFC-376) we developed a new lsst/templates repository model that takes advantage of Jinja2 and cookiecutter to let us be more precise and deliberate with our templates. The design calls for examples that show rendered files and projects as built by Jinja2/cookiecutter. These examples are committed directly to the templates repo. We need to ensure that the examples stay in sync with the templates, however.

We can implement that with a build system that renders the templates into the lsst/templates repo. Developers of templates can run the build system to refresh examples, and a CI system can also run the build system to ensure that the committed examples are up-to-date.

The build system should be a very simple harness for Jinja2/cookiecutter. Scons might fit the bill, or even Makefiles.

This ticket will implement that system, hook it up to CI for checking, and document how to use it.