Deprecate `VirtualObjectHandle` and all other classes that are used to
implement objects with virtual methods in the execution environment.
Additionally, the code is updated so that if the
`VTKm_NO_DEPRECATED_VIRTUAL` flag is set none of the code is compiled at
all. This opens us up to opportunities that do not work with virtual
methods such as backends that do not support virtual methods and dynamic
libraries for CUDA.
The ArrayPortalWrapper is used for both execution and control portals.
When it was wrapped around a control portal that does not work on CUDA
devices, we were getting ugly warnings even though the intention was
only to use it in the control environment.
