Configuration: Fix getPathValue() with $default=NULL

git-svn-id: https://simplesamlphp.googlecode.com/svn/trunk@3051 44740490-163a-0410-bde0-09ae8108e29a

lib/SimpleSAML/Configuration.php

@@ -430,6 +430,10 @@ class SimpleSAML_Configuration {
 			$path = $this->configuration[$name];
 		}
 
+		if ($path === NULL) {
+			return NULL;
+		}
+
 		return $this->resolvePath($path) . '/';
 	}