Allow definition of custom config directory.

To allow "clean" checkouts of Minify we could use the possibility to define a custom config directory outside the minify directory.

Using this patch a user can define MINIFY_CUSTOM_CONFIG_DIR on a new page outside the minify directory and then include minify's index.php on that page and point their rewrites etc. there instead.

The config.php (and config-test.php) could be copied to the custom directory and edited without causing svn:external/git:submodule conflicts.

min/index.php

@@ -9,11 +9,17 @@
 
 define('MINIFY_MIN_DIR', dirname(__FILE__));
 
+if (defined('MINIFY_CUSTOM_CONFIG_DIR')) {
+    define('MINIFY_CONFIG_DIR', MINIFY_CUSTOM_CONFIG_DIR);
+} else {
+    define('MINIFY_CONFIG_DIR', MINIFY_MIN_DIR);
+}
+
 // load config
-require MINIFY_MIN_DIR . '/config.php';
+require MINIFY_CONFIG_DIR . '/config.php';
 
 if (isset($_GET['test'])) {
-    include MINIFY_MIN_DIR . '/config-test.php';
+    include MINIFY_CONFIG_DIR . '/config-test.php';
 }
 
 require "$min_libPath/Minify/Loader.php";
@@ -69,4 +75,4 @@
 } else {
     header("Location: /");
     exit();
-}
+}