This fixes the path to source files in some unit tests and allows
to get rid of a few duplicate lines.

* Drawing and put_figchar methods now can handle utf8 chars.

* Bind caca_render_canvas function.
* Add example font.

* Add example figfont

* get_canvas method now return Python Canvas object.

* Add exceptions for missing methods.

bindings.
  * Distribute the python/ subdirectory using automake.

caca_set_display_time() and caca_get_display_time() for consistency.

remove redundencies in the Doxygen documentation.