#14 PATCH: CVS 2013-04-20 check-iana.sh POSIX

[Jari Aalto]

This patch is against CVS 2013-04-20 check-iana.sh

- Use /bin/sh. The file is POSIX compliant now.
- Instead of ${var}, simplify variabled to $var.
- Send errors to STDERR, normal messages to STDOUT.
- Prefer POSIX $() to archaic backquotes `` [1]
- Prefer simple [ "$var" ] and [ ! "$var" ] test. The -n and -z
tests are not needed.

[Jari Aalto]

check-iana.sh POSIX