deepCopy() functions require additional safety checks

The deepCopy() functions within the various data structure classes need some additional checks to address the following:
- It is possible to end up with null pointer objects in the hierarchy if a deepCopy() fails, even when the "top level" object is non-null.
- There is no capability to force prevent allocation of objects outside of the DataArray deepCopy().

These issues can be addressed by passing in a flag variable that can be cascaded down through the deepCopy() chain to allow for checking of success. Additionally, a boolean variable can be added that allows the deepCopy() functions to force no allocation if desired.