fixed 'Decimal' and 'float' errors..

File "check_mssql_server.py", line 292, in calculate_result
self.result = round((float(self.query_result[0]) / self.query_result[1]) * self.modifier, 2)
TypeError: unsupported operand type(s) for /: 'float' and 'Decimal'

----

File "check_mssql_server.py", line 328, in calculate_result
self.result = round(((new_val - old_val) / (new_time - old_time)) * self.modifier, 2)
TypeError: unsupported operand type(s) for /: 'Decimal' and 'float'