update gem system to prevent errors with some gems

diff --git a/.travis.yml b/.travis.yml
index 4bc9c05b4594fbd4446194968edbb4f7c9b8d42f..090896f91b5eb42a4cc0ee607f62bdf1b69ac993 100644 (file)
--- a/.travis.yml
+++ b/.travis.yml
@@ -2,6 +2,7 @@ sudo: required
 dist: trusty
 language: ruby
 before_script:
+- gem update --system
 - npm install -g eslint
 rvm:
 - 2.0.0