Used proper hierarchy for Parameters by introducing a BaseParameter class.
Fixing CRS setup for mapserver coverage layers.
Fixing passing of subset polygons.
Fixing XPath selectors for WCS 2.0 POST handlers.
Fixing default indices for WCS handlers.
Removing debug print.
Trying to fix referenceable dataset renderer. WiP.
Improved error message for 2 exception classes.
Updating autotest.