Methods comp part2: initial commit-task#491-,accuracy and closest training stations, multisampling etc.

Method comp part1 -task#491, major clean up, production of boxplots and visual maps

Initial commit-task#491-methods comparison part 1: kriging, GAM, GWR, FUS, CAI

Accuracy and spatial distance to closest fitting stat., intial commit task #491

Multi sampling kriging raster prediction, initial commit, task #491

Multisampling Kriging function interpolation initial commit raster prediction task #491

Method comparison initial commit task #491

GAM FUSION, multi sampling function initial commit

GAM FUSION, multi sampling accuarcy assessment main script initial commit

GWR, raster pred. modification model 8, function