Add missing aborts and typehints for sdoclient

[samsamfire]

Hi, I found some missing aborts whilst doing some tests: in particular, an sdo abort should be sent when a timeout occurs (0x05040000) an abort should also be sent if the expected command value is not correct (0x05040001).

I also added typehints were possible.

Also, have any of you considered to add a static type checker (mypy,...) and a linting tool ? Could be good in the future

[samsamfire]

reverting the PDO change that has nothing to do with this PR

[acolomb]

@samsamfire Sorry for not responding for such a long time. I've tried to grasp your changes here in order to see if there's merit in merging it for the next release. However, it is quite convoluted between actual changes and formatting. Would you mind separating those into several smaller PRs or at least split into independent commits?