PyUSB alpha 1 released

This release implements more PyUSB 1.0 features towards beta stage. The new
features implemented include:

- Standard control requests through usb.control module.
- Request current configuration from device when you do not call
set_configuration.
- get_string function in the usb.util module to get string descriptors.
- Full 0.4 API emulation.
- Device is not reset anymore in test cases to avoid problems in systems
where it does not work.

Features not implemented
------------------------

- OpenUSB support.
- Isochronous transfer.