BoundsError with violin and boxplot using Data

[ValdarT]

Trying to use boxplot or violin with Data, for example:

iris = RDatasets.dataset("datasets", "iris")
boxplot(Data(iris), :SepalLength)

gives BoundsError.

It works fine if values for x are added manually, e.g.:

boxplot(Data(iris), fill(1,150), :SepalLength)

[piever]

I see, so the idea is that if there is no x data, it should be default to a constant variable equal to 1? See #66