Removing Slim Extras from composer

Herp don't need the slim extras for this demo app since all
templating will be rendered in the client.

Author: jcarouth

composer.json

@@ -1,6 +1,5 @@
 {
     "require": {
-        "slim/slim": "1.6.*",
-        "slim/extras": "1.0.*"
+        "slim/slim": "1.6.*"
     }
 }