Resimplified API again.
Fixed test issues.
Refactored some common aspects.
Fixed tests.
Changed implementation to throw ArithmeticException instead of MonetaryEx in case of under-, overflow.
Fixed issue, where arguments with higher scales are not accepted (this is a case where implicit rounding must be supported).
Merge pull request #31 from otaviojava/master

Removing autoboxing, Delete jsr354-ri.iml.
Fixed useless check.