Added FIRST; --help; environment var options
FIRST lets you control the first PARALLEL_JOBNO (instead of always starting from 1). This is useful when you do something like '$((PARALLEL_JOBNO % 10))' to select one of 10 different cases in the job, so that you can restart exactly where you left off, instead of always having to restart at case '1'. Added --help argument (also HELP, -h, -?) to display full help. Bad/no arguments now displays a short usage message without the help details. Allowed HOSTS, PER_HOST, and FIRST to be set through environment variables, prefixed with PARALLEL_, e.g. $ export PARALLEL_FIRST=27 $ parallel-runner 10 'echo hi' now does the same thing as: $ parallel-runner FIRST=27 10 'echo hi' Command line arguments have highest precedence, then env vars, then file vars.