to operate with overset
1) Adding zoneMotion to rigidBodyMotion
2) Introducing PID to prescribedRotation restraint
3) Making drivenLinearMotion read total displacement
4) When drivenLinearMotion is used sixDof and rigid-body solvers
write total displacement
- previously introduced `getOrDefault` as a dictionary _get_ method,
now complete the transition and use it everywhere instead of
`lookupOrDefault`. This avoids mixed usage of the two methods that
are identical in behaviour, makes for shorter names, and promotes
the distinction between "lookup" access (ie, return a token stream,
locate and return an entry) and "get" access (ie, the above with
conversion to concrete types such as scalar, label etc).
ENH: defaulting for destructors where possible
STYLE: clear() instead of setSize(0) for plain Lists
STYLE: use bool operator instead of valid()/empty() for autoPtr tests
1) Add softWall rigidBody restrain
2) Add linearSpringDamper sixDoF restrain to work as soft rope
3) dynamicMotionSolverListFvMesh changed to dictionary based input
4) Add Time reference access to sixDof restraints
5) Add drivenLinearMotion to solidBodyMotionFunctions.
