prepared the 1.20.0 release

CHANGELOG

@@ -1,4 +1,4 @@
-* 1.20.0 (2015-XX-XX)
+* 1.20.0 (2015-08-12)
 
  * forbid access to the Twig environment from templates and internal parts of Twig_Template
  * fixed limited RCEs when in sandbox mode

ext/twig/php_twig.h

@@ -15,7 +15,7 @@
 #ifndef PHP_TWIG_H
 #define PHP_TWIG_H
 
-#define PHP_TWIG_VERSION "1.20.0-DEV"
+#define PHP_TWIG_VERSION "1.20.0"
 
 #include "php.h"
 

lib/Twig/Environment.php

@@ -16,7 +16,7 @@
  */
 class Twig_Environment
 {
-    const VERSION = '1.20.0-DEV';
+    const VERSION = '1.20.0';
 
     protected $charset;
     protected $loader;