strings-helper: Filter out duplicate strings

All ELF binaries processed by strings-helper will now have duplicated
strings filtered out.  In practise optimisation will apply to all
(normal) ELF files.  ELF files with (e.g.) ":" in their filenames will
be skipped though.

A quick test on /bin/ls suggests that we can save quite a few "lines"
and bytes doing this (~400 lines/27% and ~2.5k bytes/12%).

Signed-off-by: Niels Thykier <niels@thykier.net>
coll/unpacked: Support (literal) "a\\b" files

As far as evil path names goes, "\.\./\.\./\.\./" is not too bad.

Signed-off-by: Niels Thykier <niels@thykier.net>
t: Fix FTBFS with new dpkg due to invalid build-profiles

Signed-off-by: Niels Thykier <niels@thykier.net>
t: Update coverage and add missing tags in "Test-For"

Signed-off-by: Niels Thykier <niels@thykier.net>
t/runtests: Explicitly mention if t/scripts had failures

Signed-off-by: Niels Thykier <niels@thykier.net>
FrontendUtil.pm: Don't clean HOME + XDG_* variables when sanitizing the environment

Signed-off-by: Axel Beckert <abe@deuxchevaux.org>
debian/control: Add a Homepage header pointing to https://lintian.debian.org/

Signed-off-by: Axel Beckert <abe@deuxchevaux.org>
Add myself to debian/copyright

Signed-off-by: Axel Beckert <abe@deuxchevaux.org>
c/menu-format.pm: Refactor the loop for finding desktop files

Signed-off-by: Niels Thykier <niels@thykier.net>
c/menu-format: Retire old check for kdelnk files

The tag is no longer emitted.  Furthermore, the last KDE 1 and 2
releases were over 12 years ago, so these files are unlikely to
reappear again.

Signed-off-by: Niels Thykier <niels@thykier.net>
private/TODO: Remove obsolete TODO item

Signed-off-by: Niels Thykier <niels@thykier.net>
d/changelog: Reorder some entries

Signed-off-by: Niels Thykier <niels@thykier.net>
po4a: Update pot and po4a*.cfg files

Signed-off-by: Niels Thykier <niels@thykier.net>
Release Lintian/2.5.30 into unstable

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