Travis CI: use [openjdk8] instead of [oraclejdk8]
diff --git a/.travis.yml b/.travis.yml
index 3c67709..e7d25a5 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -18,9 +18,7 @@
 

 jdk:

   - openjdk7

-  - oraclejdk7

-  - oraclejdk8

-  - oraclejdk9

+  - openjdk8

   - openjdk11

 

 after_success: