Add fontconfig-ultimate-20141123
Rewrite Fontconfig NixOS module

Details:
* The option `fonts.enableFontConfig` has (finally) been renamed
  `fonts.fontconfig.enable`.
* Configurations are loaded in this order: first the Fontconfig-upstream
  configuration is loaded, then the NixOS-specific font directories are
  set, the system-wide default configuration is loaded, and finally the
  user configuration is loaded (if enabled).
* The NixOS options `fonts.fontconfig.defaultFonts.monospace`,
  `fonts.fontconfig.defaultFonts.sansSerif` and
  `fonts.fontconfig.defaultFonts.serif` are added to allow setting the
  default system-wide font used for these generic faces. The defaults
  are the appropriate faces from the DejaVu collection because of their
  comprehensive Unicode coverage, clean rendering, and excellent
  legibility.
* The NixOS option `fonts.fontconfig.antialias` can be used to disable
  antialiasing (it is enabled by default).
* The options `fonts.fontconfig.subpixel.rgba` and
  `fonts.fontconfig.subpixel.lcdfilter` control the system-wide default
  settings for subpixel order and LCD filtering algorithm,
  respectively.
* `fonts.fontconfig.hinting.enable` can be used to disable TrueType font
  hinting (it is enabled by default).
  `fonts.fontconfig.hinting.autohint` controls the FreeType autohinter.
  `fonts.fontconfig.hinting.style` controls the hint style; it is "full"
  by default.
* User configurations can be disabled system-wide by setting
  `fonts.fontconfig.includeUserConf = false`. They are enabled by
  default so users can set Fontconfig options in the desktop environment
  of their choice.
Load default Fontconfig settings into Xresources for Xft
Add NixOS module for fontconfig-ultimate

Details:
* The option `fonts.fontconfig.ultimate.enable` can be used to disable
  the fontconfig-ultimate configuration.
* The user-configurable options provided by fontconfig-ultimate are
  exposed in the NixOS module: `allowBitmaps` (default: true),
  `allowType1` (default: false), `useEmbeddedBitmaps` (default: false),
  `forceAutohint` (default: false), `renderMonoTTFAsBitmap` (default:
  false).
* Upstream provides three substitution modes for substituting TrueType
  fonts for Type 1 fonts (which do not render well). The default,
  "free", substitutes free fonts for Type 1 fonts. The option "ms"
  substitutions Microsoft fonts for Type 1 fonts. The option "combi"
  uses a combination of Microsoft and free fonts. Substitutions can also
  be disabled.
* All 21 of the Infinality rendering modes supported by fontconfig-ultimate
  or by the original Infinality distribution can be selected through
  `fonts.fontconfig.ultimate.rendering`. The default is the medium style
  provided by fontconfig-ultimate. Any of the modes may be customized,
  or Infinality rendering can be disabled entirely.
Replace Bitstream Vera fonts by DejaVu in defaults

The default configuration installed the Bitstream Vera fonts, but DejaVu
is a superior replacement, and the default Fontconfig settings need it
now for the generic faces monospace, sans-serif, and serif.
nixos: let fontconfig default fonts be lists of fonts
fontconfig: include user config through NixOS module
fontconfig-ultimate.rendering: correct typo in ultimate-lightest
Merge branch 'fontconfig-ultimate'