chromium: Update stable and beta channels.

stable: 24.0.1312.69 -> 24.0.1312.70 (builds fine, tested)
beta: 25.0.1364.68 -> 25.0.1364.84 (builds fine, tested)

Signed-off-by: aszlig <aszlig@redmoonstudios.org>
python-pyserial: Add new package with version 2.6.

Signed-off-by: aszlig <aszlig@redmoonstudios.org>
python-pyglet: Add new package with version 1.1.4.

This involved a bit of patching, because pyglet is searching libraries at
runtime, so we hardcode the library paths into pyglet/lib.py.

Signed-off-by: aszlig <aszlig@redmoonstudios.org>
chromium: Update dev channel to v26.0.1410.5.

The upgrade currently doesn't involve the -lite package, as we need to use a few
more dependencies from nixpkgs first before we can finally fully switch over to
the lite package, even though the update script will try to fetch it anyway.

In this update, one particular problem that arises in conjuction with the
seccomp BPF sandbox is caused by this commit:

https://chromiumcodereview.appspot.com/12209029

Which particularily filters flags to the clone() syscall. I've spent (wasted?) a
few hours figuring out the troublesome flag, eventually figuring it out and -
just by curiousity ("Do other distributions have the same problem?") - searched
the web for "chromium CLONE_DETACHED" and BEHOLD...

A post from our OWN mailinglist pops up with the same patch I intended to do:

http://article.gmane.org/gmane.linux.distributions.nixos/10356

So shame on me for not being subscribed to the mailing list, and big thanks to
Ian Farmer for the patch.

As a consequence I'm now subscribed.

So, back to chromium itself, version 26 builds fine and works so far without
much (more to come in later commits) trouble.

We also had to introduce three more dependencies:

 * protobuf: This one is because we don't need to use the bundled one anymore,
             so we can use the version in nixpkgs.
 * speechd: Not sure whether this was bundled or not, but let's use nixpkgs
            version as well to keep down build time.
 * libXdamage: Needed for screen capturing support.

Signed-off-by: aszlig <aszlig@redmoonstudios.org>