LUCENE-5909: Smoke tester now has better command line parsing and optionally also runs on Java 8

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1621473 13f79535-47bb-0310-9956-ffa450edef68
LUCENE-5909: Fix description

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1621479 13f79535-47bb-0310-9956-ffa450edef68
LUCENE-5909: Fix stupid bug

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1621486 13f79535-47bb-0310-9956-ffa450edef68