Various improvements and bug corrections: fixed ndvi pixel clipping, adjusted memory requirement calculation, added one variable (footprint) for pixel GIF plotting. Other small changes.

Fixed irrigation equations. Small readability and performance updates. Changes in input preparation.

Modification of SAMIR equations, use of Kcbmax instead of Kcmax. Plot_GIF modifications. Doc update.

Further improvements in optimization. Manage to create real empty output dataset and append values along the time dimension, greatly improves total run speed. Reworked the custom_input notebook for a better handling of the land cover class conversion. Added tests on parameters values to make sure they are in correct range, parameter ranges are defined in a csv file (params_samir_min_max.csv). Other small modifications.