Very experimental. Probably very broken. Adds support for newer
models but removes it for some older ones.

Hence not the default yet, if ever.

From building reflex-dom (which has quite a few dependencies), it would
appear that building the documentation no longer fails.

Tested with a Samsung CLP-325. Here goes nothing.

Dwarf Fortress updates

Theme can be specified either as a derivation or as a string, in which
case it will be taken by name from a pre-defined set of themes available in
nixpkgs.

Also specify license, see https://github.com/fricy/Phoebus/issues/5

This is a massive rework of the current dwarf_fortress package.
The main reason for rework is to split game, its libraries and wrappers,
enabling builds on Hydra and general maintainability.

dfhack, dwarf-fortress-unfuck, dwarf-fortress-original and dwarf-fortress
are now all separate derivations. All were updated to the latest versions
supporting DF 0.42.04 (some things taken from development branches):

dfhack: 20150927 -> 20160118
dwarf-fortress-unfuck: 0.40.24 -> 20160118
dwarf-fortress-original: 0.40.24 -> 0.42.05

dfhack got a patch for using more system libraries.

Wrapper scripts were also redone -- now they support DF_DIR variable (for
setting another data directory) and try to save more space by means of
symlinking. They now try to be more smart, updating those directories that were
not touched by user automatically.

All the new packages now reside in dwarf-fortress-packages. dwarf_fortress was
renamed into dwarf-fortress per our conventions, old name is deprecated. Also
duplicate dfhack derivation is removed.

Also drop dwarfFortress.enableDFHack config option; it can be re-added later
but now is deemed controversial.

Standalone flashplayers

Gateone: fix cacerts dependency

This will probably be mandatory soon, and is a step in the right
direction. Removes the deprecated meta.version, and move some meta
sections to the end of the file where I should have put them in
the first place.

Also refactor meta.
Maybe we could have platforms.all in there, but I leave it here.

NixOS manual: allow options from nix packages

nixos-ssh: set SSH_ASKPASS globally and not just on interactive shells

vcunat moved `version` into the derivation.

Ruby fixes

This was preventing any ruby gem with a c extension to build.

mkmf would fail with a misleading error:

    /nix/store/dmkcai8fnv21qxiasx628nim3mq4r4wg-ruby-2.2.3-p0/lib/ruby/2.2.0/mkmf.rb:456:in `try_do': The compiler failed to generate an executable file. (RuntimeError)
    You have to install development tools first.

generate_stub doesn't exist and the output is not used in the code so I just
removed the line.

This was preventing the binstubs from generating properly.

Set dontStrip when building ghcjs libs, which fixes the ghcjs-dom lib
and also makes the logs cleaner.

kdbplus bump

solaar: init at 0.9.2