tpp design decisions:

1. visualizer

The visualization of a slide is done by a visualizer. Visualization in the context of tpp
means outputting it to an output device, e.g. a terminal via ncurses, a LaTeX source file,
a Docbook source file, you name it. The generic TppVisualizer is the base for all visualizers.
Look at the source which methods you need to implement if you want to write your own
visualizer.

2. controller

the controller handles the correct output, utilizing the parser and a visualizer. The generic
TppVisualizer is the base for all visualizers. All controllers must implement a constructor,
and the two methods run and close.