expose endianness and float representation

[ToSa27]

The API seems to lack the ability to get the endianness and float format information from e.g. the connect requests. With the stack not executing any data manipulation (which I think is the right design choice), the application layer would need to know these details to properly assess the content. For now I'm working with S7-1500 which appears to always leverage little endian and IEEE float representation but as the protocol supports different options I would want the app to be able to react to different scenarios.

[pyhys]

Thanks for this enhancement proposal. I think it would be a great feature.