Updates to fix gem for logstash

Logstash will not pull the java fix correctly during its build for two reasons:
1. The gem version for filewatch specified in the logstash.gemspec is 0.5.1, this fix will not get pulled without bumping the version above that.
2. The jar file is in the wrong place in the gem structure for logstash to pick it up in the build - it needs to be underneath lib instead of java