haskellPackages.dbmigrations: New expression
gcc: Fix build error on gcc 4.7

Specifically, we are trying to fix the following error seen on Hydra:

../../gcc-4.7.3/gcc/gengtype-lex.c:1:21: fatal error: bconfig.h: No such file or directory

The patch is taken from gcc's SVN revision 193691.
Merge pull request #1518 from wizeman/u/gcc_47_bconfig

gcc 4.7 build fix attempt
eclipse: Remove patchelf from the buildInputs
Revert "acl: update from 2.2.51 to 2.2.52"

This reverts commit 16d0ee024e66fc6081522a761e0feaaa1b6dbe09.

This is already in stdenv-updates.
bind: update to version 9.9.4-P2
qjackctl: add meta.platforms
drumkv1: update from 0.3.5 to 0.3.6

http://monitor.nixos.org/patch?p=drumkv1&v=0.3.6
haskell-blaze-markup: update to version 0.5.2.1
haskell-ghc-mod: update to version 3.1.5
haskell-shelly: update to version 1.4.1
haskell-snap-core: update to version 0.9.6.0
haskell-snap-server: update to version 0.9.4.0
haskell-snap: update to version 0.13.2.0
haskell-wai-extra: update to version 2.0.2
haskell-warp-tls: update to version 2.0.1
haskell-warp: update to version 2.0.2
Allow specifying extra qemu flags using QEMU_OPTS. Replace CentOS 6.3 with CentOS 6.5 (6.3 is removed from site).
haskellPackages.websocketsSnap: New exppression
haskellPackages.httpStreams: New expression