- set() was silently deprecated in favour of reset() FEB-2018
since the original additional check for overwriting an existing
pointer was never used. The reset(...) name is more consistent
with unique_ptr, tmp etc.
Now emit deprecations for set().
- use direct test for autoPtr, tmp instead of valid() method.
More consistent with unique_ptr etc.
STYLE: eliminate redundant ptr() use on cloned quantities
