Delete columns and/or colors.

        Method wraps::

                tabular.spreadsheet.deletecols(self, cols)

def deletecols(self, cols):
        """
        Delete columns and/or colors.

        Method wraps::

                tabular.spreadsheet.deletecols(self, cols)

        """
        if isinstance(cols, str):
        	cols = cols.split(',')
        deletenames = utils.uniqify(utils.listunion([[c] if c in 
        self.dtype.names else self.coloring[c] for c in cols]))
        return spreadsheet.deletecols(self,deletenames)