Replace the JDK8 placeholder by use of java.time package.


git-svn-id: https://svn.apache.org/repos/asf/sis/branches/JDK8@1587364 13f79535-47bb-0310-9956-ffa450edef68
Skip JDK8-specific change.


git-svn-id: https://svn.apache.org/repos/asf/sis/branches/JDK7@1587365 13f79535-47bb-0310-9956-ffa450edef68