gdd smartCopy from empty array returns out-of-bounds error

[Ralph Lange]

Found while poking at spurious messages in the CA Gateway logs:

When copying arrays, the gdd::put() method (being called from the gddAppTable's smartCopy() function) returns an out-of-bounds error if the index of the first source element to copy is equal or larger than the source array size.

This fails when copying from an empty array, where size and first element to copy are zero. Instead, that case should not be considered an error.