fix intDiv div operation and more edge cases with precision for all arithmetic operations

[jennifersp]

IntDiv does operations in decimal type values and returns the int part of the decimal value result. If the value goes out of bound of int64, it errors.

Fixed few more edge cases for all arithmetic operations including:

• any time type value gets parsed as int value with pattern of YYYYMMDDHHMMSS or YYYYMMDD depending on what's defined. This applies to all arithmetic operations.
• invalid string tries to parse available numbers from the beginning of the string value and used in the arithmetic operation. 12.4ag3.2jgw499 is parsed as number 12.4, and a942.6ng488 is parsed as 0.

[fulghum]

Looks good! Only one small suggestion about using a little more regex in one place to simplify your parsing code.