patch stumpy to support crystal 0.35

[da1nerd]

Someone already created a PR for this stumpycr/stumpy_png#29

[bararchy]

*someone 😢

[da1nerd]

@bararchy some very special person worthy of immense honor and recognition. Just not when I'm quickly writing up an issue before going to sleep. 😛

[bararchy]

ahahahha @neutrinog i'm kidding ofc :) happy it helped you, I'm following your project with zeal, I'm aching to try it soon in building some game.

[da1nerd]

The core feature that caused this break is being reverted. See crystal-lang/crystal#9469