private static Catalog get(ResourceRef ref) {
		Catalog catalog;
		Path catalogPath = ref.getFile();
		if (Util.isFresh() || !catalogCache.containsKey(catalogPath.toString())) {
			catalog = read(ref);
			catalog.catalogRef = ref;
			catalogCache.put(catalogPath.toString(), catalog);
		} else {
			catalog = catalogCache.get(catalogPath.toString());
		}
		return catalog;
	}
Returns a Catalog containing all the aliases from local catalog files merged
into one. This follows the system where aliases that are "nearest" have
priority.

@param includeImplicits Determines if the implicit catalogs should be merged
                        or not
@return a Catalog object
src/main/java/dev/jbang/catalog/Catalog.java