LMR download lock (#1314)
LMR download lock (#1314)

add download lock for multiprocessing LMR data
anoukvlug/oggm,bearecinos/oggm,TimoRoth/oggm,OGGM/oggm,TimoRoth/oggm,juliaeis/oggm,OGGM/oggm,juliaeis/oggm,bearecinos/oggm,anoukvlug/oggm