check getopts letters and secret keys
Check the command line and secret conventions of scripts.

conform-conventions reads shell scripts that call getopts and example files. It
names a reserved letter in the wrong shape, a missing -h, a -h that writes on
standard error, a long option, and a secret key that holds a value in an
example. It reads files only.

Maintainer: Jean-Gerard Pailloncy <j-g@pailloncy.com>
