…ons in _constraints based on discussions with Josh and Mohammad

…ser defined constraints and examples on how to implement it

…on to be greater than the optimal number suggested by plain QR and example notebook reflecting the same

…w changes for the constraints class), addressing Josh's comments on this class and notebooks reflecting all of the functionalities of this class

… way user defined constraints are plotted for various string,equation implementations

…l as being able to plot on multiple axes for plot_constraints_on_data and subsequent plotting functions. Adding different colours to annotate_sensors and plotting_selected_sensors to reflect effect of constraints on sensors selected. Jupyter notebooks updated to reflect these changes

…tion as the matplotlib ellipse function requires the diameter or the vertical and horizontal axis and we were giving it half_major_axis and half_minor_axis)

…ction() of class Ellipse(), the functional_constraints_class notebook reflects these chnages