NaturalNode/natural — pull request #70 by joscha (2012-09-27 10:02:29+00:00)
Title: ignore empty documents

When calling

`classifier.addDocument("","someClass");`
or
`classifier.addDocument([],"someClass");`

there is no real value added, as the class gets added to the classifier, but there is no data to base any classification on - ergo probability for this class will always be 0% - this pull request fixes this by not adding the empty data at all and thus making sure that the classifier does not get unnecessarily bloated.