Create unit in namespace.
function initialize(dest, declarations, name, cache, inited) {
        var decl = declarations[name];
        if (!inited[name]) {
            // Create unit dependencies first.
            var len = cache.dependencies[name].length;
            for (var i = 0; i < len; i++) {
                initialize(dest, declarations,
                        cache.dependencies[name][i], cache, inited);
            }
            // Create unit.
            decl._init(dest, name);
            inited[name] = true;
        }
    }