Fix lots of bugs in the numeric interface and tests.
Tests:
* Coerce a result to bool to deal with Python's new Bool type
* Better reporting of mismatches in expected and received results
* Remove bogus nullary y.astype() call
* Fix all uses of trace and diagonal so they don't cause errors
* Use appropriate typecodes
* Use doctest detailed API to run just the relevant tests
* Factor out error handling from macro
API:
* Added get_module_name() function to get current numeric module
* new_(x) now returns an array instead of object
* Fixed the signatures of the factory() family of functions
* Updated docs accordingly.
[SVN r35528]
Dave Abrahams