Feature 10574

The following has been done for DapMath:

1. Implemented operator ** (networking)
2. Operator // (integer division) implemented
3. Implemented operator % (Taking the remainder of division)
4. Add the fToCoins attribute - it should convert the value into Datoshi and convert it into a Python float, the conversion is done through an integer delente by 10**18
5. Add a helper method taking N% of DapMath.
6. Added description of new and old methods to the core.pyi interface file