renice: reorder functions to avoid need of function prototype

Signed-off-by: Sami Kerola <kerolasa@iki.fi>
rename: use usage and version print out macros

Signed-off-by: Sami Kerola <kerolasa@iki.fi>
renice: disallow --priority <arg> without pid argument

Earlier a lonely priority with an argument but without pid resulted to no
action and success, when the invocation should have failed.

$ renice --priority 42 ; echo $?
0

Signed-off-by: Sami Kerola <kerolasa@iki.fi>
renice: avoid having same lines of code twice

Add getprio() function to avoid duplication of a simple task.

Reviewed-by: Karel Zak <kzak@redhat.com>
Signed-off-by: Sami Kerola <kerolasa@iki.fi>
renice: fix numeric uid argument parsing

The following was inconflict with what usage() tells are valid option
arguments.

$ renice 1 -u 1000
renice: unknown user 1000
$ id
uid=1000(kerolasa) ...

Reviewed-by: Karel Zak <kzak@redhat.com>
Signed-off-by: Sami Kerola <kerolasa@iki.fi>
rename: add getpriority() message lookup table

Signed-off-by: Sami Kerola <kerolasa@iki.fi>
renice: reorder usage() option descriptions

Make the Usage: and Options: sections to be in same order, which I found
to be quicker to use than alphabetical order.

Signed-off-by: Sami Kerola <kerolasa@iki.fi>