Cant read or write in 0.4.0 s71200 tia portal v14

[yusuflars]

![Screenshot_1](https://user-images.githubusercontent.com/61707883/75705232-09757d80-5ccc-

11ea-9b26-2e14e0685cad.png)

Always getting "IndexOutOfRangeException"

[zoltraks]

This might be cause by not having "Protection & Security" option "Permit access with PUT/GET communication from remote partner" checked.

I have also put a Pull Request with small fix for that:

#258

[mycroes]

Please retest against 0.7.0, that release includes fixes for partial responses which previously led to IndexOutOfRangeExceptions.

[mycroes]

Closing, feel free to reopen if the issue persists.