Brew install github url is disabled by default

[vinyll]

➜ ~ git:(master) ✗ brew install https://raw.githubusercontent.com/EricChiang/pup/master/pup.rb

Updating Homebrew...
==> Auto-updated Homebrew!
Updated 1 tap (homebrew/core).
==> Updated Formulae
Updated 1 formula.

Error: Calling Non-checksummed download of pup formula file from an arbitrary URL is disabled! Use 'brew extract' or 'brew create' and 'brew tap-new' to create a formula file in a tap on GitHub instead.

I guess the readme should be updated

[gromgit]

PR was submitted over 18 months ago (#116), so don't hold your breath.

[vinyll]

brew install pup is the way to go.

Thanks @gromgit for the path.