added DuplicatesDetector.getUniqueValues()
name cleanup in DuplicatesDetector
refactored CommandLineParser to use DuplicatesDetector.getUniqueValues()
added Streams.inputStreamToByteArray()
added test to StreamsTest
changed Streams.copy() to not wrap IOException into FileSystemException
added tests to StreamsTest checking that streams are closed
fixed JarFunction to close all streams correctly