Use autoCopy when copying vector blocks

Open lh1887 requested to merge feature/use_autocopy into master

This way, types that implement AutonomousValue can specify into what type they are copied. This can be applied e.g. for proxy types such as the BlockVectorWindow used in ISTL's VariableBlockVector.

For types that do not implement AutonomousValue, the behavior should not change.

Merge request reports