Update rubygems to fix travis in ruby 1.8

Carlos Sanchez · Carlos Sanchez · commit 958c428a2034 · 2014-01-14T10:24:53.000+01:00
diff --git a/.travis.yml b/.travis.yml
@@ -50,3 +50,6 @@ notifications:
     on_success: always
     on_failure: always
     use_notice: false
+
+before_install:
+  - gem update --system #  todo: workaround for https://github.com/rubygems/rubygems/pull/763
