Update README.md

Author: simonhamp

README.md

@@ -5,15 +5,19 @@
 You can install the package via Composer:
 
 ```bash
-composer require nativephp/php-bin
+composer require nativephp/php-bin --dev
 ```
 
 or NPM:
 
 ```bash
-npm -i @nativephp/php-bin
+npm -i @nativephp/php-bin --save-dev
 ```
 
+### ℹ️ Heads up...
+> You should install this package as a `dev` dependency, in most cases, and simply copy what you need from it to the
+relevant parts of your application. This will save you distributing all of the PHP binaries with every installation.
+
 ## Credits
 
 - [Marcel Pociot](https://github.com/mpociot)