Update README.md
Fixes #225
Homebrew no longer maintains cask-fonts, it is currently empty and deprecated. So, after installing Homebrew, simply run brew install <font>.
I know that there is an active PR #228 awaiting merge. It's been more than a few months since we heard back from the author. Also, the current usage is brew install <font> per the official doc. Explicit cask is not needed anymore for installation purposes since homebrew-cask is rewritten as an extension of Homebrew. These days it's primarily used for searching for casks exclusively or getting an exclusive local list of casks.
@Finii can you please review and approve?
Thank you for the review @Finii @idan could you please review and merge.
@colebemis
closed by #272 — thank you!