nixos/graphite-service: fix startup issue

The preStart snippets (graphite, carbon) try to create directories under
/var/db/. That currently fails because the code is run as user
"graphite". Fix by setting "PermissionsStartOnly = true" so that the
preStart stuff is run as 'root'.

Further:
 * graphite-web-0.9.12/bin/build-index.sh needs perl, so add it to PATH.
 * Now that preStart runs as root, we must wait with "chown graphite"
   until we're done creating files/directories.
 * Drop needless check for root (uid 0) before running chown.
nixos/grahite-service: mkdir -m => mkdir && chmod

mkdir -m will only set the permissions if it *creates* the directory.
Existing directories, with possibly wrong permissions, will not be
updated.

Use explicit chmod so permissions will always be correct.
herbstluftwm: update to 0.6.2
jdk7: update patchversion 51 -> 55.
Bump mpv to 0.3.8
Add subtitle option for ffmpeg.
Fix whitespace
libmx: Add package
eigen: upgrading version to 3.2.1
libgnurl, a fork of libcurl used by GNUnet
gnunet: add libgnurl and GnuTLS as dependencies

libgnurl is essential for bootstrapping (needed to download a hostlist).
GnuTLS is needed by gnunet-gns-proxy.

Also sort dependencies alphabetically.
Creation of a new package for texstudio, an editor for LaTeX documents
Add the necessary preConfigure so that TeXstudio compile (find poppler-qt4.h)
Cleaning up the description and fixing qt to qt4
Adding myself as maintainer of texstudio
spark: 0.9.0 -> 0.9.1

Signed-off-by: Austin Seipp <aseipp@pobox.com>
firefox: Update to 29.0
Remove the option ‘programs.bash.enable’

NixOS has a pervasive dependency on bash. For instance, the X11
session script sources /etc/profile to get a reasonable
environment. Thus we should not provide an option to disable bash.

Also, enabling zsh no longer sets ‘users.defaultUserShell’ to zsh, to
prevent a collision with bash's definition of the same
option. (Changing the default shell is also something that should be
left to the user.)
xfce: fix typo introduced in recent commit (s/gtk/gtk3/)

Fix typo introduced in commit 0b2dd3a12fca27a185f9c5518acb7d73d140e1e5
(Xfce: Don't depend on GTK+ 3 by default).
haskell: new expression cabal-bounds