Medium changes related to new messages & warning, and extremas of axes on graphs
Improvement of the management of messages (in the code, no changes for the user). and addition of new output messages related to the results of the model fitting (MSY & MSE values and their confidene limits, visibility of the lines corresponding to fitted values for noteworthy values of V in the 3D graphs). Management of the access to the MSY-MSY graphs in the "Plots" menu when they are not available (CPUE=f(V) and abnormal results on MSY & MSE values or width of the confidence intervals). Improvement of the management of extremas of axes in the different plots.