Cleaned up vtkSMArrayListDomain and vtkSMInputArrayDomain.

vtkSMInputArrayDomain no longer depends on a required property to decide the
field association. That was relevant in ParaView 2.0 days when we used separate
UI widgets to pick array association and array name. This simplifies
vtkSMInputArrayDomain considerably. Fixed vtkSMInputArrayDomain::AttributeTypes
to match vtkDataObject::AttributeTypes. The mismatch was unnecessary and
confusing.

Cleaned vtkSMArrayListDomain to simplify interaction with vtkSMInputArrayDomain.
Now vtkSMArrayListDomain can work without any vtkSMInputArrayDomain specified on
the required Input property. Default setup logic in vtkSMArrayListDomain wasn't
respecting the attribute_type correctly (due to misinterpretation of overloaded
term 'attribute'). Fixed that.

vtkSMStringListDomain no longer has public API to change the domain. We will
update other domains to follow the same pattern.

Change-Id: I6d44a29cb1763b84f2b9d80c03c72da314f2d616