public static Catalog getBuiltin() {
		Catalog catalog = Catalog.empty();
		if (Util.isFresh() || !catalogCache.containsKey(CACHE_BUILTIN)) {
			String res = "classpath:/" + JBANG_CATALOG_JSON;
			ResourceRef catRef = ResourceRef.forResource(res);
			if (catRef != null) {
				catalog = read(catRef);
				catalog.catalogRef = catRef;
				catalogCache.put(CACHE_BUILTIN, catalog);
			}
		} else {
			catalog = catalogCache.get(CACHE_BUILTIN);
		}
		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