This is a very minimalistic example in which just a few functions
and constants from library are wrapped and used to draw some simple
shapes.  

`make' will build a version of Guile which defines an additional
module (simple).  Run `./simple-guile -s runme.scm' to test it.

`make dynamic' will build a dynamically loadable module, which can be
loaded from any Guile interpreter.  Run `guile -s runme.scm' to test
it.  The `use-modules' call in `runme.scm' dynamically loads the
module. 
