This example tests the %import directive and working with multiple modules.

Use 'python runme.py' to run a test.

Overview:
---------

The example defines 4 different extension modules--each wrapping
a separate C++ class.

     base.i     -  Base class
     foo.i      -  Foo class derived from Base
     bar.i      -  Bar class derived from Base
     spam.i     -  Spam class derived from Bar

Each module used %import to refer to another module.  For
example, the 'foo.i' module uses '%import base.i' to get
definitions for its base class. These modules do not generate
any runtime code (-noruntime commandline option).

The runtime.i file is an empty SWIG module which will generate
the runtime library code for sharing amongst the other modules 
(uses -runtime commandline option). 

If everything is okay, all of the modules will load correctly and
type checking will work correctly.

Unix:
-----
- Run make
- Make sure your LD_LIBRARY_PATH includes the current directory so that
  lib_runtime.so can be loaded.
- Run the test as described above

