More refactoring
More refactoring

Split off create_mosaic_dir and modified comment. Still no change to logic.

modified:   stacker.py

ama-jharrison/agdc,sixy6e/agdc,ama-jharrison/agdc,jeremyh/agdc,jeremyh/agdc,GeoscienceAustralia/agdc,smr547/agdc,smr547/agdc,sixy6e/agdc,alex-ip/agdc,alex-ip/agdc,GeoscienceAustralia/agdc