Major changes on Arbre_decision, QuestionReponse, TexteRegles, about stock structure and level of exploitation.

Major changes to incorporate new messages regarding the stock structure and the level of explotation relative to MSY-MSE. Introduction of the metapopulation concept. Elimination of a redondant questions regarding stock structure when chosing between linear (Schaefer) and exponential (Fox) models.
Minor changes: Comment.csv, comments into .java files, new CLI test file.