Todo: Support Adding Twig Extensions

[sghoweri]

Todo: Support Adding Twig Extensions

[EvanLovely]

Done. Doable like so:

https://github.com/basaltinc/twig-renderer/blob/master/__tests__/twig-extensions/twig-extensions.js#L9-L12

You can pass a series of php files and there functions to call that get passed what you see here:

https://github.com/basaltinc/twig-renderer/blob/master/__tests__/twig-extensions/alter-twig.php

and since you get passed the whole Twig Env, you can do whatever that can do; one of them being adding Twig Extensions.