Replacing pON with SFS

[8char]

Although I haven't personally used SFS yet outside of this repo, it appears to be an overall better alternative to pON based on the project's readme. SFS boasts significant improvements in both speed and efficiency for data compression. It also looks to render the current util.Compress function obsolete when SFS is utilized (As util.Compress would only increase the size). Integrating SFS compression should be easy as a drop in replacement by the looks of how you've implemented pON in to gm_express so far.

[sarahsturgeon]

Fantastic, thank you!
I had been wanting to do this since I saw srlion's original post, but I've been completely overwhelmed with responsibilities, I haven't had time to give any of my projects the love they deserve 😭

I would love to use this as the impetus to get the #37 PR merged finally (be sure to try that one out if you haven't already!)

I'm just heading to bed now, but I'll do all the legwork to get this merged before the weekend 👍 💯