[travis] Add jdk 15/16

hazendaz · hazendaz · commit a847d8b94328 · 2020-09-20T21:36:45.000-04:00
diff --git a/.travis.yml b/.travis.yml
@@ -1,6 +1,8 @@
 language: java
 
 jdk:
+  - openjdk16
+  - openjdk15
   - openjdk11
   - openjdk8
 
