Improvment of module hydrograph, code optimization and bug fixes
(1) In module “hydrograph”, change the function name “generate_figure” to “generate_hydrograph”
(2) Moved “best_fit_waterlvl” from “WHAT” to “GraphParameters” class in “hydrograph” module.
(3) Moved “best_fit_time” from “WHAT” to “GraphParameters” class in “hydrograph” module.
(4) In “select_closest_meteo_file” in “WHAT”, updated the variable lat and lon to LAT and LON.
(5) In “generate_hydrograph” in module “hydrograph”, added “fig.patch.set_facecolor('white')”
(6) Added the code to test the module “hydrograph” outside of the GUI