update README.md

Author: wakeful

README.md

@@ -4,6 +4,18 @@ A small tool for converting YAML files into JSON.
 
 ## Installation 
 
+macOS
+```
+$ brew tap wakeful/selection
+$ brew install yaml2json
+```
+
+Linux
+```
+curl -Lo yaml2json https://github.com/wakeful/yaml2json/releases/download/0.1.0/yaml2json-linux-amd64 && chmod +x yaml2json && sudo mv yaml2json /usr/local/bin/
+```
+
+src
 ```
 go get -u github.com/wakeful/yaml2json
 ```