Fix for PQ mosaic issue with weird no-data values. stacker.py updated to use contiguity bit to determine which pixels contain data in mosaic source tiles. Data pixels will be bitwise-anded with eachother, while non-contiguous pixels will be bitwise-ored with eachother. After all data pixels have been populated, non-data pixels will be set to the new value.
Fix for PQ mosaic issue with weird no-data values.
stacker.py updated to use contiguity bit to determine which pixels contain data in mosaic source tiles. Data pixels will be bitwise-anded with eachother, while non-contiguous pixels will be bitwise-ored with eachother. After all data pixels have been populated, non-data pixels will be set to the new value.

Single commit (855ea8) merged into hotfix 0.1.3 as a bug-fix.

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