Update to Java source/target version 6.

Enable testing on JDK 9. To aid this, updated jacoco plugin dependency to latest version which is JDK9-compatible.

Author: mikesamuel

.travis.yml

@@ -5,7 +5,7 @@ jdk:
 # - openjdk6 # No longer supported by Travis
  - openjdk7
  - oraclejdk8
-# - oraclejdk9 # Not testable on JDK9. Something maybe related to Jacoco mucking with the bootclasspaht
+ - oraclejdk9
 
 # Additionally pass -Dgpg.skip to suppress signing instead of trying to provision
 # Travis's containers with keys.

parent/pom.xml

@@ -177,8 +177,8 @@ application while protecting against XSS.
  <artifactId>maven-compiler-plugin</artifactId>
  <version>3.3</version>
  <configuration>
- <source>1.5</source>
- <target>1.5</target>
+ <source>6</source>
+ <target>6</target>
  </configuration>
  </plugin>
  <plugin>

pom.xml

@@ -23,7 +23,7 @@
  <plugin>
  <groupId>org.jacoco</groupId>
  <artifactId>jacoco-maven-plugin</artifactId>
- <version>0.7.5.201505241946</version>
+ <version>0.7.9</version>
  <configuration>
  <destFile>${basedir}/target/coverage-reports/jacoco-unit.exec</destFile>
  <dataFile>${basedir}/target/coverage-reports/jacoco-unit.exec</dataFile>