Pr upstream

[odeke-em]

This PR provides improvements to the original code:

• help.Usage:
  • This is necessary to match the behaviour of common Unix usage where programs can take: prog -h, prog --help, prog help, prog -help, prog --h. Otherwise fla.Parse exits upon encountering -h, could define flag.Usage but we need to maintain the behaviour or passing arguments to the help function.
• stdout is now the outfile descriptor instead of stderr: This is allow for users to pipe content into filters as well as to search for strings e.g using grep <a_prog_using_command> -h | grep -i keyword [keywords....]
• help: stable sort order for subcommands: Makes the program help output more familiar and more easily indexed without minimal differences in case it changes, otherwise everytime there will be changes.