Enable mcrypt, intl and exif support in PHP
php: Add xsl optional support

Use an override with xsl = true to enable xsl support in php.
php: Add mcrypt optional support

Use an override with mcrypt = true to enable libmcrypt support in php.
The --disable-posix-threadsds mcrypt build option was required by php.
php: Add zip and optional bz2 support

Use the overload bz2 = true to enable bz2 support for php.
zip support is enabled by default as it doesn't require any library.
compile fix: <stddef.h> needed for size_t
x11vnc: Fix more hard-coded /bin/su
urbanterror: Update to 4.2.009.
urbanterror: Correction for previous commit.
all-packages.nix: Uncomment e17.
iwlwifi-4965 fix download url
pngcrush: update to fix compilation with libpng-1.6.*
httpie: fix
Fix Hydrogen to build with JACK 1.9.9.5

This patches the Hydrogen scons build script to work a failure to
parse the JACK version correctly. If I understand correctly upstream
Hydrogen now uses cmake instead of Scons, so this shouldn't be a
problem with the next Hydrogen release.
x86info: fix
linphone: minor update and fix
minidlna: Update to 1.0.25 and use ffmpeg instead of libav
mediastreamer: forgotten update needed for linphone
vmime: fix via minor update
e17.embryo: Fix meta.

Meta attributes, if they are lists, must be lists of strings.
Add wayland library