use trusty dist for travis-ci build

fbourigault · fbourigault · commit 533032292639 · 2017-06-06T21:35:27.000+02:00
diff --git a/.travis.yml b/.travis.yml
@@ -2,6 +2,8 @@ language: php
 
 sudo: false
 
+dist: trusty
+
 cache:
     directories:
         - $HOME/.composer/cache/files
