FilterToSQL: try converting to Number before converting to String
CompareFilterImpl: Handle case where both values are strings that can be cast to numbers
FilterToSQL: try converting to Number before converting to String

CompareFilterImpl: Handle case where both values are strings that can be cast to numbers
Undo change to SLDStyleFactoryTest
Some additional tests for comparing numbers/strings
Fix Bridj unit test. The overridden setup methods needs to call super.
Add unit test for reading and writing GeoRSS. Includes bug fix for Bridjs support for String arrays and the removal of LayerCanCreateField check because the GeoRSS driver return false even though it needs to create fields when writing
Add unit test for reading the writing SQLite. Includes fix to sorting when using database based drivers that pass SQL straight through and thus dont have access to FID which is OGR SQL. Also adds LayerGetFIDColumnName to the OGR interface.
Add unit tests for writing and reading several formats: GeoJSON, CSV, GMT, GPX.  Updated GML and KML tests to make sure reading is working too.
Add environmental variables to the maven surefire plugin to make it easier to run unit tests
[GEOT-4656] AverageVisitor and MedianVisitor fail on null value
Exclude georss, gpx, sosi from the can create field check due to gdal bug
Merge pull request #355 from NielsCharlier/geopkg

Geopackage Mosaic Reader
[GEOT-4684] Build failure in geopkg GeoPackageReaderTest caused by bad File-URL conversions
[GEOT-4685] SLDStyleFactory graphic rasterization does not honor the rendering hints field
[GEOT-4686] WMSCoveageReader can return coveage bounds with no CRS
[GEOT-4687] Build failure in gt-svg DrawTest caused by visibly different image
[GEOT-4688] SimplifyingFilterVisitor should simplify and-ing/or-ing of negated filters
Fixing test, and also a bug in wfs store, attributes used in post filters were not being requested to the remote wfs
Check for references when removing a coverage on Imagemosaic (Related to GEOT-4640)
[GEOT-4691]: NetCDF envelope fix (corner coordinates)