Add 20_autoreconf.diff by Andreas Barth to let autoreconf run successfully
and use dh-autoreconf. Closes: #759719

Use debhelper v9 compat, bump build-dep. Drop unneeded invocation
of dpkg-buildflags.
Update *.install.
Add Pre-Depends: ${misc:Pre-Depends}.
Runtime library is Multi-Arch: same, cmd-line utils Multi-Arch:
foreign.

nonlinuxlargestack.diff Fix FTBFS when large stacks are disabled.
Bug-report, diagnosis and patch by Pino Toscano. Closes: #680509

Use 'dpkg-buildflags --export=configure' to get hardening-flags.
(Thanks, Moritz Muehlenhoff). Add required b-d on dpkg-dev (>= 1.16.1).
Closes: #656506

Change override_dh_auto_test target to invoke dh_auto_test, otherwise
the testsuite is run twice. (Once for build and binary).

Use dh --with autotools_dev. Version autotools-dev
build-dependency.

openexr does not contain a viewer, update package short description.
Closes: #471783

Any sane PDF viewer should be able to handle decompression.