* First go at IndependentDistributionOutput, subclassed by NormalOutput and NegativeBinomialOutput for now
* Multivariate test for new implementation of NormalOutput
* adding scaling parameter to NormalOutput
* IndependentNormalOutput now is an alias of NormalOutput with a DeprecatedWarning. Some more univariate distributions now inherit from IndependentDistributionOutput
* IndependentNormalOutput now is an alias of NormalOutput with a DeprecatedWarning. Some more univariate distributions now inherit from IndependentDistributionOutput