[OpenAFS-Doc] Subcommand help text

[Jeff Blaine]

1.  Do we have a line-length restriction for help text
     provided for each subcommand arg?  "don't resolve
     addresses" for -noresolve, as an example

2.  Is there a way to provide an auxillary short block
     of help text at the end of the output shown for
     a subcommand?  Example, but not going to do it here:

Usage: vos examine -id <volume name or ID> [-extended] [-format]
          [-cell <cell name>] [-noauth] [-localauth] [-verbose] [-encrypt]
          [-noresolve] [-help]
Where: -extended   list extended volume fields
        -format     machine readable format
        -noauth     don't authenticate
        -localauth  use server tickets
        -verbose    verbose
        -encrypt    encrypt commands
        -noresolve  don't resolve addresses
Notes: blah blah blah blah