Drop Java 9, 12, 13 from Travis CI.
@@ -21,22 +21,12 @@ matrix:
jdk: openjdk7
- dist: trusty
jdk: openjdk8
- - dist: xenial
- jdk: openjdk10
- dist: xenial
jdk: openjdk11
- dist: trusty
jdk: oraclejdk8
- - dist: trusty
- jdk: oraclejdk9
- dist: trusty
jdk: oraclejdk11
- - dist: trusty
- jdk: oraclejdk12
- - dist: trusty
- jdk: openjdk12
- - dist: trusty
- jdk: openjdk13
- dist: trusty
jdk: openjdk14
- dist: trusty
