bison: add version 2.6
all-packages.nix: bump default version of 'bison' from 2.5 to 2.6
all-packages.nix: comment-out obsolete bison versions 2.3, 2.4, and 2.5

After a reasonable grace period, these packages should be removed.
bash: Update to 4.2-p37
glibc: setting --enable-kernel=2.6.35

It was taking 2.4.0 as default, therefore, not using syscalls over 2.4.0
We may see performance improvements (openat, ...)
glibc: fixing the glibcLocales build

It was stopping hydra from evaluating further, I think. I broke it
in my previous commit.
release: Disabling hydra builds of now non-existant bison versions

It breaks the evaluation of stdenv-updates by hydra.
release-small: make hydra evaluate fine for stdenv-updates

In my previous commit I didn't know it was using release-small, instead
of release.nix.
stdenv-updates: merge updates from 'master' branch
Clean up changes to the Cabal builder, which needed to be done in an awkward fashion to avoid a complete re-build of all Haskell packages.
Remove duplicate attribute
Remove unused files
Remove obsolete Glibc versions
glibc: Update to 2.16
Fix some packages that referred to gets()

Glibc no longer defines gets() if _GNU_SOURCE is defined.
gzip: Update to 1.5

This fixes the gets() problem in gzip.

Also disabled "make check" because it depends on Perl and more/less,
which is undesirable in the stdenv bootstrap.
ed: Update to 1.6
patch: Update to 2.7
coreutils: Update to 8.19
gnugrep: Update to 2.14