General cleanup in WMS code. 'options' dictionary is now passed to connectors as-well and includes the 'subset' in case of WMS GetMap.
Merge branch '0.4' into wms-improvements
Added new 'MultiParameter' that collects multiple KVP parameters at once. Adding 'elevation' and arbitrary dimensions to WMS GetMap parser for version 1.1 and 1.3.
Adding performance measurement utilities.
Adding width and height as render options.
Removed debug print.
Adding additional fields for the Band model to allow the specification of the minumum and maximum expected values of each band.
Adding min/max band values to rangetype serializer/deserializer.
Fixing admin for range types.
Merge pull request #292 from ESA-VirES/wms-improvements

Small improvements to WMS handler and renderer code