doc,man: Fix typos

Signed-off-by: Niels Thykier <niels@thykier.net>
c/fields.pm: Quote package names used in regex

Signed-off-by: Niels Thykier <niels@thykier.net>
coll: Stop creating empty "*-errors" files

bin-pkg-control, unpacked and index creates "error" files for the
STDERR output from tar.  However, often there is no output on STDERR
leaving these files empty, so remove them in that case to save a
few inodes per entry.

Signed-off-by: Niels Thykier <niels@thykier.net>
coll/hardening-info: Do not unconditionally create file

Quite a few packages have no hardening issues left (e.g. most arch:all
packages).  Instead of creating an empty file to signal this, have
L::C::Binary handle the absence of the file.

Signed-off-by: Niels Thykier <niels@thykier.net>