Use NodeJS built-in crypto

[alexopenkowski-the-nu-company]

warning multipassify > crypto@0.0.3: This package is no longer supported. It's now a built-in Node module. If you've depended on crypto, you should switch to the one that's built-in.

[fbushell]

Is there any movement on this? There is an open PR for it here → #4 from 2018. Any chance we can get this merged in?

CC: @corymsmith @achinn