Fix bzgrep so it doesn't always return a 0 exit code with multiple archives
The bzgrep wrapper always returns 0 as exit code when working on
multiple archives, even when the pattern is not found.
Fix from openSUSE by Kristýna Streitová <kstreitova@suse.com>
https://bugzilla.suse.com/970260
Fix bashism in bzgrep
bzgrep uses ${var//} which is a bashism.
Replace by calling sed so other POSIX shells work.
Patch from openSUSE by Led <ledest@gmail.com>
