use julia 0.6

bicycle1885 · bicycle1885 · commit 5f76e4d38f87 · 2017-06-04T18:40:33.000+09:00
diff --git a/.travis.yml b/.travis.yml
@@ -4,7 +4,7 @@ os:
   - linux
   - osx
 julia:
-  - release
+  - 0.6
   - nightly
 notifications:
   email: false
