Add some numeric tests


[SVN r7984]
Added some testing for numeric type support


[SVN r7985]
*** empty log message ***


[SVN r7986]
Some more testing for numerics support


[SVN r7987]
Numerics support


[SVN r7988]
Numerics support. Clean up some flotsam, also.


[SVN r7989]
Convert doubles to_python.


[SVN r7990]
Remove unimplemented Tuple constructors, and add some others for convenience.


[SVN r7991]
Numerics support.


[SVN r7992]
Factor out exception-handling. Add numerics support.


[SVN r7993]
Fix description of ComputedAttribute feature for accuracy.


[SVN r7994]