npm: move 'npm install -g' to the top

pages/common/npm.md

@@ -3,14 +3,14 @@
 > JavaScript and Node.js package manager.
 > Manage Node.js projects and their module dependencies.
 
-- Download all dependencies referenced in package.json:
-
-`npm install`
-
 - Download and install a module globally:
 
 `npm install -g {{module_name}}`
 
+- Download all dependencies referenced in package.json:
+
+`npm install`
+
 - Download a given dependency, and add it to the package.json:
 
 `npm install {{module_name}}@{{version}} --save`