Better device permissions handling

Prints which device failed due to permission denied.
Does not attempt to print garbage when permission denied.
Prints an error message when no devices can be accessed.

Devices to be configured with different permissions for different users. eg User backup can power on the backup disk only.

Python interface added

Now uses a library with python interface. The command line tool uses the library and works in the same manner as before.

Added ability to change serial number

Added ability to change the serial in non volatile memory. Use the fictitious relay 0 to take up to 5 characters as the new serial. eg:

$ sudo usbrelay OLD_0=NEW

Serial is now NEW and can be immediately used.

Added return codes for errors

Error states such as relays not found now return >0 error codes which can be tested for in scripts.
The return code is the number of errors found

Support modules with different number of relays

A device that has 8 relays but fundamentally is the same device emerged.
It is clear that the USBRelay2 or USBRelay8 Product signifies the number of relays in the particular module.

This release extracts the number of relays and displays the correct number, rather than being hard coded to 2.

The software has been tested with 2 and 8 relay modules and should handle 1 and 4 relay modules. At present the software extracts a single character for the number of relays.

Release for Debian packaging

v0.1

Add GPL License