adding brew install tap

[paulvollmer]

it should be helpful to install the tool via brew

[BigOokie]

@paulvollmer I have created a PR which I hope might get you started with this. I have tested it running from my Fork and it works - in that it installs the binary from your v0.3.1 release - however MacOS is reporting to me that the binary is not executable (there was no file extension so I am unsure what it is).

Anyway, I hope the files included in the PR assist to get a working homebrew installation working for you
Please let me know if you have any questions.