Correct npm install to --save-dev

I believe devDependencies are more appropriate here.
travco · Oct 17, 2017 · b1273d2 · b1273d2
1 parent c909411
commit b1273d2
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/README.md b/README.md
@@ -50,7 +50,7 @@ In regards to the concerns people have with Sass's `@extend`, and the problems t
 
 ## Installation
 ```
-npm install postcss-extend --save
+npm install postcss-extend --save-dev
 ```