fix docs for sub and add and make error message more descriptive

cullophid / date-fp

Functional programming date manipulation library

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fix docs for sub and add and make error message more descriptive #12

Closed svozza closed 8 years ago

svozza commented 8 years ago

Docs gave incorrect time units for D.add and D.sub. Error messages weren't very descriptive so they now give the user a list of of the valid units.