NHIRS-148: Using queue instead of massive number of threads to avoid hitting system thread limit.
NHIRS-148: Removed invalid gdal import. Re-organised imports.
NHIRS-148: Removed unnecessary usage of threading in some places.
NHIRS-148: FlushCache added on each 1% progress and at the end.
NHIRS-148: Using queue instead of massive number of threads to avoid hitting system thread limit. NHIRS-148: Removed invalid gdal import. Re-organised imports. NHIRS-148: Removed unnecessary usage of threading in some places. NHIRS-148: FlushCache added on each 1% progress and at the end.