Allos OCP classes to be PSR-4 as well

This adds the OCP namespace to the composer autoloader as well.
This means that now we can use proper PSR-4 filenames in OCP.

composer.json

@@ -3,7 +3,10 @@
         "vendor-dir": "lib/composer"
     },
     "autoload" : {
-        "psr-4": {"OC\\": "lib/private"}
+        "psr-4": {
+            "OC\\": "lib/private",
+            "OCP\\": "lib/public"
+        }
     },
     "require-dev": {
         "jakub-onderka/php-parallel-lint": "^0.9.2",

lib/composer/composer/autoload_psr4.php

@@ -7,4 +7,5 @@ $baseDir = dirname(dirname($vendorDir));
 
 return array(
     'OC\\' => array($baseDir . '/lib/private'),
+    'OCP\\' => array($baseDir . '/lib/public'),
 );