Fix travis javax/xml/bind/JAXBException.

Travis switched it's default jdk from 8 to 11 in the last year.
LanguageTool 2.2 is not compatible with later jdk's without workarounds.

Author: ryneeverett

.travis.yml

@@ -9,6 +9,12 @@ python:
     - "3.6"
     - "nightly"
 
+before_install:
+    - sudo apt-get -y install openjdk-8-jdk
+    - export PATH=/usr/lib/jvm/java-8-openjdk-amd64/jre/bin:$PATH
+    - ls /usr/lib/jvm/java-8-openjdk-amd64/jre/bin
+    - java --version
+
 install:
     - if [ "$TRAVIS_PYTHON_VERSION" == "2.7" ]; then pip install 3to2; fi
     - python setup.py install