linux: Update to 3.12.21

(cherry picked from commit 246edc3df2ade0701aabc53e41d6c8c85f51ac24)
mariadb: 10.0.10 -> 10.0.11

Also, enable the TokuDB plugin, as it now builds (there were some bugs
in the non-GA release that prevented that).

Signed-off-by: Austin Seipp <aseipp@pobox.com>
(cherry picked from commit 463ed1bb640efcd3b3714a67e94800a6003eb320)
kernel/grsec: updates; add mainline package for brave souls

Signed-off-by: Austin Seipp <aseipp@pobox.com>
(cherry picked from commit b43421221ff3ea7069de175845be80075f31d2a8)

Conflicts:
	pkgs/top-level/all-packages.nix