CLN/API: Refactor of _get_numeric_data/_get_bool_data to core/generic.py, allowing Series/Panel functionaility
CLN: cleaned up numeric dtype tests in tools/plotting.py
Merge pull request #4675 from jreback/numeric

CLN/API: Refactor of _get_numeric_data/_get_bool_data to core/generic.py, allowing Series/Panel functionaility