using previous image

Weiwei Wang · Weiwei Wang · commit 72794a3b70a5 · 2017-12-19T13:53:22.000+08:00
diff --git a/.travis.yml b/.travis.yml
@@ -1,5 +1,8 @@
 sudo: required
 
+dist: trusty
+group: deprecated-2017Q4
+
 services:
   - docker
 
@@ -8,4 +11,4 @@ script:
 
 notifications:
   email:
-    on_failure: always
+    on_failure: always
