Merge pull request #149 from herbygillot/patch-1

readme: add MacPorts installation info

Author: PaddiM8

README.md

@@ -32,9 +32,12 @@ Kalker is a calculator program/website that supports user-defined variables, fun
 
 ## Package managers
 
-### macOS
+### macOS (Homebrew)
 `brew install kalker`
 
+### macOS (MacPorts)
+`sudo port install kalker` ([info](https://ports.macports.org/port/kalker/))
+
 ### Arch Linux
 `kalker` in the AUR, eg. `yay -S kalker`