Use non-throwing new for %new_copy etc

[ojwb]

This makes the behaviour for C and C++ consistent since now NULL gets returned which gets mapped to Null, None, etc in the target language.

Fixes https://sourceforge.net/p/swig/bugs/1372/

[wsfulton]

This is a major API breakage for everyone who expects std::bad_alloc to be thrown and has special exception handling in place to catch this exception. I've put this kind of code in place in a various places.

Alas, the control and handling of out of memory isn't a good story in the generated wrappers. If there are any changes made in this area, it should be part of a comprehensive documented plan for consistency and filling gaps and options for handling non-throwing and throwing new.

[ojwb]

I've put this kind of code in place in a various places.

It'd be useful to at least document how to do that then.

[wsfulton]

The kind of things I meant is using %exception to catch bad_alloc to handle out of memory in an application specific way by catching the exception, logging it and then mapping it to a particular target language exception. Similarly for throws typemaps which also handle exceptions.