Prepare version 1.1.1.

Author: bgaillard

CHANGELOG.md

@@ -5,6 +5,9 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](http://keepachangelog.com/) and this project adheres to
 [Semantic Versioning](http://semver.org/).
 
+## [1.1.1] - 2017-11-28
+* Minor fixes for PHP 5.6.
+
 ## [1.1.0] - 2017-11-28
 * Add support for expressions with simple logical operators and without parenthesis. The or operator is writen with `-`,
   the and operator is written with `+` ;