Add java-versions.properties file for CI (elastic#1474)

Author: jbaiera

.ci/java-versions.properties

@@ -0,0 +1,10 @@
+# This file is used with all of the non-matrix tests in Jenkins,
+# and is based on how the Elasticsearch project configures java
+# versions.
+
+# This .properties file defines the versions of Java with which to
+# build and test Elasticsearch for this branch. Valid Java versions
+# are 'java' or 'openjdk' followed by the major release number.
+
+ESH_BUILD_JAVA=java8
+ESH_RUNTIME_JAVA=java8