Adds a command 'create_reprojected_geotiffs'.

The tiffs are for the whole area, and for each user. Tiffs are created
based on the last 24 hours of production RD geotiffs. Older generated tiffs
are cleaned up by the script.

A setting GEOTIFF_ANIMATION_CACHE_DIR is needed to point to the directory
in which these tiffs should be generated.

The WmsView uses these tiffs to render Google projected image layers.
Record changes
Merge branch 'development'
Preparing release 0.7
Back to development: 0.8