Update README.md

--dev is marked for deprecation. I was unable to install the node modules using `npm install --dev` because it installs the devDependencies recursively, and my machine failed at that. `npm install` will will install devDependencies (except on production). See [this issue](npm/npm#6137 (comment)) for discussion.

README.md

@@ -51,7 +51,7 @@ Clone the repo, `git clone git://github.com/mgcrea/angular-strap.git`, [download
 AngularStrap is tested with `karma` against the latest stable release of AngularJS.
 
 >
-	$ npm install --dev
+	$ npm install
 	$ gulp test
 
 You can build the latest version using `gulp`.