BUG: maximum train and validation sizes were not correctly handled
(ac574321)

BUG: fix TrainImagesClassifier when bm=0.
(2a3cce86)

Now input vector with class is required for unsupervised classifier.
The cases where input vector data were optional for unsupervised
classification are commented.

Update license for added/moved files.

This allow to have only one application to handle bot supervised and
unsupervised classifier.

Classifier category is retrieve with selected classifier and depending
this category some operation are added/removed for the training.

SampleSelection can now be used without input vector data.

Create a common class with template to perform Supervised classification
(same as otbTrainImagesClassifier) or Unsupervised.

Add the ability to specify Supervised or Unsupervised classification

Inherit TrainVectorClassifier from TrainVectorBase and use Non-Virtual
Function Idiom to provide common behavior for Unsupervised and
Supervised classification.