--------------------------
NAMEFILE structure:
CZE - Czech Republic
SVK - Slovak Republic

GGFM model names:
EIGEN-6C4
EGM08
XGM2019e

W0 value:
VATRT   = 62636856.0 m^2 s^-2
SANCHEZ = 62636853.4 m^2 s^-2


special for: CLASSIC_GBVP_ISGEMS.tar
MT = Mean Tide 
rezid{RADIUS}km - radius used when computing RTM


special for: FAST_GBVP_ISGEMS.zip
RBB = Removed values beyond the borders (replaced with nodata value)
