rhbz1157359 - fix a few java client issues

- --version or -v gives no output (due to non-flushed buffered output)
- single --help or help or -h not giving a list of commands (same as above)
- --logHttp is not recognized (annotation at wrong place). Also changed it to --log-http to follow convention
- redirect will produce friendlier error message
Now I'm wondering if we even need to close stdout/stderr.  Or should.