Add support for btsync 2.x branch

postfix28 and postfix211: hardening with Canary, PIE, Full RELRO and FORTIFY_SOURCE

pandoc: fix on GHC 7.10

Slic3r dropped this dependency in v1.1.0 and we have v1.2.x.

And more importantly, BoostGeometryUtils is currently broken (fails on
newer Perl versions), so this patch unbreaks Slic3r.

cpanm is one of three(?) CPAN clients, see
http://stackoverflow.com/questions/5861292/which-cpan-installer-is-the-right-one-cpan-pm-cpanplus-cpanminus.

Generated with "nix-generate-from-cpan App::cpanminus", plus I added
platforms = all;

Signed-off-by: Austin Seipp <aseipp@pobox.com>

Version 1.22 is broken on newer Perl ("Out of memory" test failures).

 Bug #121948 for perl5: Bleadperl breaks Math-Clipper-1.22.tar.gz ("Out of memory")
 https://rt.perl.org/Public/Bug/Display.html?id=121948

Teamviewer

Check if /proc/sys/kernel/hotplug exists before writing

ecryptfs 104 -> 106

Signed-off-by: Austin Seipp <aseipp@pobox.com>

Rebuild impact seems low, except for LibreOffice.

Updating source url

Fixes minetest mesa 10.* incompatibility, adds minetest server service

If a kernel without CONFIG_UEVENT_HELPER set is used with NixOS, the file
/proc/sys/kernel/hotplug does not exist. Before writing to it to disable
this deprecated mechanism, we have to ensure it actually exists because
otherwise the activation script will fail.

postfix: Update from 2.11.3 to 2.11.4

v4l-util: refactor & 1.0.0 -> 1.6.2 (libv4l)

youtube-dl: update from 2015.03.24 to 2015.04.03

evopedia: version bump to 0.4.4

kid3: update from 3.1.1 to 3.1.2

nilfs-utils: package hash changed

GRC: 1.7 -> 1.9

Updated GNU APL to 1.5

Added mailcheck, simple utility to check for mail.