[patch] First shot at fixing up the proxy call chain

[John (J5) Palmieri]

This patch pulls the logic from ProxyObject.__getattr__ and puts it into
ProxyMethod.__call__ and DeferedMethod.__call__.  It still retains the
dbus_interface keyword for working with Interface objects which call
__getattr__ directly.

Right now we block in the DeferedMethod but I will be adding back the
async queue code in the future.

One thing that has to be looked at is the timeout which occurs when no
interface is given.  I ran into this again while testing and not having
the Interface object hooked up correctly.  I believe it might just be
HAL and objects python creates, coincidentally handling no-interface
methods wrong.  In other words I don't think we are returning
DBUS_HANDLER_RESULT_HANDLED correctly.

-- 
John (J5) Palmieri <johnp at redhat.com>