Bug#253012: check for common POSIX violations in /bin/sh scripts

[Clint Adams]

Package: lintian
Version: 1.23.0
Severity: wishlist

lintian should check /bin/sh scripts for matches to expressions similar
to the following, and scream bloody murder if they're found.

test .*-[ao].
command -v.
kill -[0-9A-Z]