GEOT-4358: added FilterFunction isCoverage
GEOT-4358: added test
GEOT-4364 [2]: fix parsing LiteralOutput/DataType with null ows:reference
GEOT-4367
GEOT-4367
Merge pull request #107 from simboss/GEOT-4367

Fix for GEOT-4367
Merge pull request #104 from etj/master

GEOT-4364 [2]: fix parsing LiteralOutput/DataType with null ows:reference
Merge pull request #96 from svzdvd/upstream-is_coverage

GEOT-4358: added FilterFunction isCoverage
[GEOT-4267] Some filter functions do not cast arguments to numeric types
[GEOT-4363] Respect LatLon CRS Axes Order in GeoTiff plugin