A tag is added (as for confidence output) to all ML models.
Implementation only for Shark RF.

STY: Change ITK_OVERRIDE for override in whole code (find Modules -type f -exec sed -i 's/ITK_OVERRIDE/override/g' {} +)

This reverts commit 9bd55905.

Update license for added/moved files.

Move commons files for both supervised and unsupervised into
LearningBase Module.
Also update Test and includes.