Add - again a very simplistic - method for themeing the output.
Essentially, the plan is to have JSON-formatted configuration files in
bumblebee/themes/ and have a separate class for querying the config
whenever the output needs to know about semantic formatting/coloring.
Note that the theme object is stored on a per-module basis. Right now,
that doesn't have any effect (except looking particularly wasteful), but
the idea is to be able to have different themes for different modules in
the future.
Add a very simplistic framework for loading modules that query system
data. The user can provide a list of modules via an argument switch, and
the name of the module is used to look up a Python module that has to
have a class called "Module".
The outer framework (the outputs, in particular) then uses various query
methods of that class to construct a meaningful output.
