Money version 2.0.3

Bug Fixes

• Fixes the typespec for Money.new/2 and revises several other typespecs. Added a dialyzer configuration. Since Money.new/2 allows flexible (probably too flexible) order or arguments, the typespec does not fully match the function implementation and Dialyzer understandably complains. However the value of a typespec as documentation argues against making the typespec formally correct. This will be revisited for Money 3.0.