* the urlencode filter had been renamed to url_encode
* the include tag now merges the passed variables with the current context by default
(the old behavior is still possible by adding the "only" keyword)
+ * Moved Exceptions to Twig_Error_* (Twig_SyntaxError/Twig_RuntimeError are now Twig_Error_Syntax/Twig_Error_Runtime)
+ * changed all exceptions to extend Twig_Error
* fixed unary expressions ({{ not(1 or 0) }})
* fixed child templates (with an extend tag) that uses one or more imports
* added support for {{ 1 not in [2, 3] }} (more readable than the current {{ not (1 in [2, 3]) }})