grsecurity: Update to 2.9.1-3.2.52-201311021628
grsecurity: Add patch for 3.11.x kernels
paxctl: New package

A tool for controlling PaX flags on a per binary basis.
gradm: New package

grsecurity's RBAC administration utility.
firefox: Add support for grsecurity
chromium: Add support for grsecurity
Make XFS kernel config options optional
vim: add config option to generate vimrc
Add nixopsUnstable package
XXX Workaround for grsecurity
qimageblitz: Mark stack as non-executable (patch taken from Gentoo)

This allows applications such as okular and kolourpaint to run in
grsecurity kernels, which disallow executable stacks by default.
linux: Update to 3.11.7
grsecurity: Update to 2.9.1-3.2.52-201311071633 and 2.9.1-3.11.7-201311071634