added $installer->isVerbose()

src/Composer/Installer.php

@@ -1166,6 +1166,16 @@ class Installer
         return $this;
     }
 
+    /**
+     * Checks, if running in verbose mode.
+     *
+     * @return bool
+     */
+    public function isVerbose()
+    {
+        return $this->verbose;
+    }
+
     /**
      * restrict the update operation to a few packages, all other packages
      * that are already installed will be kept at their current version