Clarify usage message.

$cmd: generate run CAVP algorithm tests

	--debug                       Enable debug output

	--dir=<dirname>               Optional root for *.req file search

	--filter=<regexp>

	--filter=<regexp>	      Regex for input files of interest

	--onedir <dirname>            Assume all components in current directory

	--rspdir=<dirname>            Name of subdirectories containing *.rsp files, default "resp"

	--tprefix=<prefix>

	--tprefix=<prefix>            Pathname prefix for directory containing test programs

	--ignore-bogus                Ignore duplicate or bogus files

	--ignore-missing              Ignore missing test files

	--quiet                       Shhh....

	--quiet-bogus                 Skip unrecognized file warnings

	--quiet-missing               Skip missing request file warnings

	--generate                    Generate algorithm test output

	--generate-script=<file>    Create shell script of test commands

	--minimal-script	    Keep script commands to a minimum

	--mkdir=<command>	    Command to make directories in scripts

	--rm=<command>	   	    Command to remove directories in scripts

	--generate-script=<filename>  Generate script to call algorithm programs

	--minimal-script              Simplest possible output for --generate-script

	--win32                       Win32 environment

	--compare-all                 Verify unconditionally for all tests

	--list-tests                  Show individual tests

	--mkdir=<cmd>                 Specify "mkdir" command

	--notest                      Exit before running tests

	--rm=<cmd>                    Specify "rm" command

	--script-tprefix              Pathname prefix for --generate-script output

	--enable-<alg>		      Enable algorithm set <alg>.

	--disable-<alg>		      Disable algorithm set <alg>.

	Where <alg> can be one of: