TODO

- Add support for building packages inside a chroot, with Mock or Iurt.

- Add support for workspace containing only one project, with everything
  in the root directory (when the projects_dir value is not set).

- When no project name is given on command line, detect the project
  to use with the current working directory.

- Add a test command. After building packages, this run some integration
  tests on the packages. This works on packages, or other files created
  by the build command.

- Add an install command, to install the package that has been built.

- Make the +d+ template variable a function that returns the distro
  config option value. Make it possible to override distro config in a
  project's config.

- Add a pkg template function that take a generic package name as
  argument, and return a distro specific package name. To do this, it
  will use the first undef value after trying in the following order :
   * if the config option +distributions/[distro]/packages+ is a hash,
     then return the value with generic package name as key
   * if the config option +distributions/[distro]/packages+ is a string,
     then use it as the package name. You could do an exec in this option,
     if you want to use a script to convert the package name.
   * return the same package name

- Write default templates for perl, python, ruby modules, and plugins
  to generate config file for modules with infos from CPAN, Python
  package index, Ruby gems, etc ... This should make it possible to
  create a package for any supported distribution, for a perl, python,
  ruby module with a single command.