Petascope expects wrong subset parameter names (WCS-KVP)

[jpass@…]

According to the WCS-KVP standard (OGC 09-147r1) the boundaries of the coverage subset shall be defined by zero or more 'subset' parameters. However petascope requests with multiple 'subset' parameters only respect the first listed subset parameter.

Eg.

the following subsetting (trim on two axes) request:

​http://earthserver.bgs.ac.uk/petascope/wcs2?service=WCS&Request=GetCoverage&version=2.0.0&CoverageId=bgs_rs&format=image/tiff&subset=x(3043,6086)&subset=y(2791,5581)&

returns the same result as:

​http://earthserver.bgs.ac.uk/petascope/wcs2?service=WCS&Request=GetCoverage&version=2.0.0&CoverageId=bgs_rs&format=image/tiff&subset=x(3043,6086)&

It appears as though petascope is following the older draft of the WCS-KVP standard (like: ​https://portal.opengeospatial.org/files/?artifact_id=36263), where the boundaries of coverage subset are defined by the parameter subsetd where d is 'some non-empty string which serves as disambiguator, i.e, makes subset keys unique within the request on hand'

E.g for our trim on two axes to work it expects a request like:

​http://earthserver.bgs.ac.uk/petascope/wcs2?service=WCS&Request=GetCoverage&version=2.0.0&CoverageId=bgs_rs&format=image/tiff&subsetA=x(3043,6086)&subsetZ=y(2791,5581)&

[upanday]

A patch is submited