Generate Float96 and Float128 if NumPy defines them.
Get Arrays atom type from the native type instead of the disk type.
Build tables columns from native data types.
Add floats float96 and float128 to the conversion table.
Add tests for extended precision datatypes.
Fix typo in test_types.py
Fixed comments in test_types.py
Fix test_types.py logic.
Merge branch 'develop' of github.com:PyTables/PyTables into andreabedini-extended_precision