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Clarify a few exceptions to carry more accurate meaning

When the last straw breaks the camel's back, the straw is not
 ObjectTooBigException, instead, the camel threw an
 NotEnoughStrengthException

Similarly, when you can't fit another penny into a jar because
 it is already full, then the jar throws a NotEnoughSpaceException
 instead of the penny complaining ObjectTooBigException