changed the osx image for travis CI.

treefrogframework · treefrogframework · commit 41014ced6d78 · 2018-03-24T22:11:58.000+09:00
diff --git a/.travis.yml b/.travis.yml
@@ -6,7 +6,7 @@ matrix:
       dist: trusty
       sudo: required
     - os: osx
-      osx_image: xcode8.3
+      osx_image: xcode9.2
       sudo: required
 
 env:
