covariates production, modification related to output and parallelization to speed up

master script, gam fusion using tensor as basis e.g. te(x,y)

master script, gam fusion additional models using s(x,y), s(x,y,LST)

gam fusion prediction, minor output path changes following debugging

data preparation, debugging, clean up of input parameters names

LST script calc, modifications to allow parallel call of python+GRASS script

download and LST calc, modification of output and downloading of South America tiles

covariates preparation script, modifications to handle LST inputs and output directory

LST processing function, test and modifications

LST processing R function, initial commit, calls to python scripts