Reduce dependency footprint of gst-python.

The gst-python package actually is perfectly happy with pygobject and
does not require pygtk.
Disable failing test case.

The test fails due to bug in the pygobject dependency.
scala: Bump up version from 2.11.2 to 2.11.4
Document likely breakage when people update the kernel.
camlimages: update from 4.0.1 to 4.1.2

Previous version 4.0.1 is kept for OCaml 3.12
Merge pull request #4759 from alexanderkjeldaas/do-not-break-grsecurity

Document likely breakage when people update the kernel.
Merge pull request #4721 from rycee/gst-python

Cleanups of legacy gst-python package
Merge pull request #4758 from vbgl/camlimages

camlimages: update from 4.0.1 to 4.1.2
mongodb: 2.6.4 -> 2.6.5
calibre: update from 2.7.0 to 2.8.0
Merge pull request #4753 from taku0/scala_2_11_4

scala: Bump up version from 2.11.2 to 2.11.4
R: update to version R-3.1.2
nix-prefetch-git: whitespace cleanup

Use 4 spaces per indent level instead of a mix of 2 spaces, 4 spaces and
hardtab. (According to nixpkgs coding style for shell scripts.)
youtube-dl: update from 2014.10.25 to 2014.10.30
nasm: update from 2.11.05 to 2.11.06
libgit2: update from 0.21.1 to 0.21.2
pwgen: update from 2.06 to 2.07
libmicrohttpd: update from 0.9.37 to 0.9.38
nix-prefetch-git: remove unneeded semicolons

Shell isn't Perl ;-)
cran-packages: update all packages to their respecitve latest version