Improved GD 2 detection (bugs #736111, #741192).

config.inc.php3

@@ -446,6 +446,13 @@ $cfg['SaveDir']               = '';         // for example, './save/'; you must
                                             // directory
 
 
+/**
+ * Misc. settings
+ */
+$cfg['GD2Available']          = 'auto';     // Is GD >= 2 available? Set to yes/no/auto. 'auto'
+                                            // does autodetection, which is a bit expensive for
+                                            // php < 4.3.0, but it is the only safe vay how to
+                                            // determine GD version.
 /**
  * SQL Parser Settings
  */