xsession: Start the right pulseaudio binary

Fixes #4663.
Merge pull request #4683 from kirelagin/xsession-pa-fix

xsession: Start the right pulseaudio binary
thunderbird-bin: update to 31.2.0
xcodeenv: make the login keychain the default, before the generated keychain gets discarded. Otherwise, the keychain becomes corrupt
titaniumenv: make the login keychain the default, before the generated keychain gets discarded. Otherwise, the keychain becomes corrupt
Added libpcap dependency and --with-libpcap configure flag to support ip address learning
slrn: update 1.0.1 to 1.0.2
fping: set meta.platforms
Merge pull request #4685 from ehmry/slrn

slrn: update 1.0.1 to 1.0.2
tzdata: set platforms to build on hydra
tomcat: set meta.platforms
aspell: set meta.platforms
Merge pull request #4684 from aycanirican/libvirt-ip-addr-learning-support

libvirt: Added libpcap dependency and --with-libpcap configure flag to support ip...
brickd: packaged version 2.1.1
Merge pull request #4687 from qknight/brickd-2.1.1

brickd: packaged version 2.1.1
Add back in args passed to buildLocalCabalWithArgs
nix-exec: bump
libxml2: 2.9.1 -> 2.9.2 (CVE-2014-3660) fixes #4679
rsnapshot: add git version & make it configurable in the nixos module
rsnapshot: add (commented) code for an idea that did not work out yet