Correct the `/tmp` directory permissions in the docker images
Remove custom Apache log files from the docker images
Removed redundant links to `epsg` and `skos` modules
Upgrade to use Mapnik v2.0 for the metadata images
Enable the localhost port of the web server to be configured

This represents the port that the webserver is running on when
accessed from localhost.  This is used in the GDAL data source used to
access the tile mapping service through a self-referencing URL. It
needs to be set if port forwarding is used to expose the application
to an external web server on a non-standard port, which otherwise
results in an invalid `SERVER_PORT` server variable (the forwarded
port is used, rather than the actual local port).
Fix the file path to the GDAL WMS data source file from the VRT

This is used in generating the background layers in the metadata
extent images.