add bash-4.2 patches 25 through 39
Merge remote-tracking branch 'upstream/master' into bash.121120
Merge remote-tracking branch 'upstream/master'
Merge remote-tracking branch 'upstream/master'
Applied to wrong branch.
Revert "add bash-4.2 patches 25 through 39"

This reverts commit b6c5b9806f6ae79652336a7cfb51fe0f03d0590a.
Merge https://github.com/jcumming/nixpkgs into master_clean
Merge remote-tracking branch 'upstream/master' into master_clean
Merge remote-tracking branch 'upstream/master' into master_clean
x86info-1.30
Merge remote-tracking branch 'upstream/master' into x86info.130109
Fix compliation of gts on Darwin
Merge branch 'master' of github.com:NixOS/nixpkgs
graphviz: Fix compilation on darwin
Update x86info description. Add Homepage.
urxvt-9.16
imagemagick: disable ghostscript on darwin, to make it work
Add the replace-dependency build support function.

The use case is to do a deep replacement of a dependency without rebuilding the entire tree.
For example, suppose a security hole is found in glibc and a patch released. Ideally, you'd
just rebuild everything, but that takes time, space, and CPU that you might not have, so in
the mean time you could build a safe version of, say, firefox with:

  firefox-safe = replace-dependency { drv = firefox; old-dependency = glibc; new-dependency = patched-glibc; };

Building firefox-safe will rebuild glibc, but only do a simple copy/string replacement on all other dependencies
of firefox. On my system (MBP 13" mid-2012), after a new glibc had been build building firefox took around 11 seconds.

See the comments in the file for more details.
Merge pull request #259 from jcumming/urxvt.130111

urxvt-9.16
Remove some artifacts of a failed attempt from replace-dependency
replace-dependency: Don't strictly require that drv, old-dependency, and new-dependency be derivations