HandlerWrapperTool: handle config arguments properly

It is possible to pass configuration variables to tools created using
HandlerWrapperTool, either via the config file, _cp_config or explicit
decorator arguments.

As HandlerWrapperTool passes these configuration variables as arguments to
the HandlerWrapperTool.callable() method, the callable method must have a
signature that actually accepts any arguments. These are not passed on to
the actual handler function, that might work with those using explicit
config.get() calls.

Signed-off-by: Balazs Scheidler <bazsi@balabit.hu>

--HG--
branch : cherrypy-3.2.x
Merged in bazsi/cherrypy/cherrypy-3.2.x (pull request #59)

HandlerWrapperTool: handle config arguments properly

--HG--
branch : cherrypy-3.2.x
Merge fix from 3.2.x