bump java version to 6
rm hint to demo command line tools
Get version from manifest via Package.getImplementationVersion()
added ID3v2.setGenreDescription(String text), fixes #6
improved tests for ID3v2Tag.setGenreDescription(String)
yet another test for ID3v2Tag.setGenreDescription(String)
Small change to test which is easier to read
Refactoring: replace verbose if/else blocks with ternary operator
Merge branch 'master' into spock_unit_testing