Firebird service:
 * simplify directory layout
 * clean up option descriptions
 * let the user override Firebird package
 * create firebird user
 * clarify TODO comment

Close  # 1061.
my-env: pull --norc shell flag out into shell parameter

As zsh's corresponding flag is called --no-rcs, the build environment
couldn't be configured to use zsh at all.

Even then the custom PS1 won't work on zsh, but it's usable enough.

Close #1040.
Update fossil to 1.27, and enable the JSON API.
sauerbraten: SVN repository has moved
Add smlnj-110.76

Based on patch by Marc Weber:
http://lists.science.uu.nl/pipermail/nix-dev/2010-December/005625.html

Close #1058.
Merge branch 'fossil127' of https://github.com/linuxfood/nixpkgs
flightgear: add .desktop file
Small fix in handling of "unfree" meta.license attributes

meta.license is can be a string or a list of strings. But there is one
unhandled case where "unfree" (or "unfree-redistributable") is a part of
a list. It will currently not be detected as an "unfree" package and
Hydra will attempt to build it. This should fix it.

Example: http://hydra.nixos.org/build/6553461
Adding desktop side of GfxTablet tablet-as-input-device Android app