Simplify, refactor, add new ops and get rid of some…

- replace Currency::$decimals with $subunitsInUnit
- remove Currency::scaleAmount() and unscaleAmount()
- get rid of static CurrencyTable
- add static Math class
- add Money::fromNumber()
- replace Money::getAmount() and getDecimals() with truncated() and fractionPart()
- add Money::mul(), div(), negated(), lessThan(), lessOrEquals(), format() ops
Generate currency .sql table
coding standard
Extracted class Integer from Money
Money objects postLoad hydratation listener
Default money ref to currency association is named 'currency' [Closes #11]
Require kdyby/doctrine
Renamed decimals to subunitsInUnit
fixed bc