Proper stop / resume capability

[Pog3k]

In order to have a real stop and resume and store states in an auxiliary we want to refactor:

• https://github.com/eclipse/kiso-testing/blob/master/src/pykiso/interfaces/dt_auxiliary.py#L259
• https://github.com/eclipse/kiso-testing/blob/master/src/pykiso/interfaces/dt_auxiliary.py#L266

Reasoning: start/stop resume etc. will always open/close connectors leading to internal auxiliary states getting lost