Django-gisserver

* Added browsable HTML views for WFS views, which can be extended/overwritten.
* Added content-disposition header to export formats, to have a proper filename.
* Added "abstract" property to field classes to provide a description.
* Consider `?SERVICE=WFS` as default for `WFSView` views.

* Added `FeatureType.show_name_field` to show/hide `<gml:name>` and GeoJSON `geometry_name`.
* Added `FeatureType.xml_prefix` so the outputted namespace prefix can be changed from "app:" to anything else.
* Added `FeatureType.xsd_type_class` so this can be overwritten easier.
* Added `XsdNode.to_python()` to support input data parsing.
* Added `GISSERVER_SUPPORTED_CRS_ONLY` to accept only the listed coordinate systems.
* Rename `is_gml` -> `is_geometry`.
* Fixes for CITE compliance testing for WFS Basic conformance:
* Added `ImplementsBasicWFS` flag in capabilities document.
* Added attribute resolving, like `gml:id` in XPath.
* Added querying support for the `gml:name` field.
* Added support to fetch multiple RESOURCEID objects in a single request.
* Fixed unwanted exception when the RESOURCEID format is invalid, empty results are returned instead.
* Fixed locator for RESOURCEID errors.
* Fixed filter type exception, now `OperationParsingFailed` instead of `InvalidParameterValue`.
* Fixed datetime and boolean comparisons.
* Fixed exception message when `<PropertyIsLessThanOrEqualTo>` receives an GML object.
* Fixed exception message for bad SRID's.
* Internal code reorganizations.

* Fixed `GetPropertyValue` calls for non-db optimized rendering.

* Added support for nested, flattened fields.
* Added support for dotted-names in field names.
* Added support for dotted-names in `model_attribute`.
* Added `GISSERVER_WRAP_FILTER_DB_ERRORS` setting for debugging filter errors.
* Added API's for easier subclassing:
* `FeatureField.xsd_element_class`.
* `FeatureField.parent` for elements in a complex feature.
* `gisserver.features.get_basic_field_type()`.
* Fixed CSV output to render datetimes as UTC, identical to GeoJSON
* Fixed bugs found by CITE compliance testing:
* Fixed support for LIKE operators on string-based foreign keys.
* Fixed `<fes:PropertyIsLike>` on numeric values, when the field is a string.
* Fixed comparison of `<fes:PropertyIs..>` when the field name and value are reversed.
* Improved error messages when using invalid comparison operators.
* Optimize feature retrieval, only fetch the actual fields being displayed.
* Compactified XML output headers.

* Added field renaming support with `field(..., model_attribute=...)`.
* Added support for WFS 1 parameters TYPENAME and MAXFEATURES.
* Improved error handling for FES filters with invalid comparisons.
* Fixed GeoJSON support for Decimal/gettext\_lazy values.
* Fixes for CITE compliance testing for WFS Basic conformance:
* Handle `NAMESPACES` parameter.
* Fix missing "application/gml+xml" output format for `GetFeature`.
* Fix namespace prefix support in filters (by stripping them).
* Fix support for `<fes:BBOX>` with a single operand.
* Fix `DescribeStoredQueries` to show the actual requested queries.
* Fix `DescribeFeatureType` compliance testing by supporting the WFS 1 TYPENAME parameter.
* Fix `GetFeatureById` response, which missed an xmlns:xsi to parse responses with "xsi:nil" values.
* Fix `GetFeatureById` to return a 404 instead of 400 for any ID syntax, including unexpected formats.
* Fix `GetCapabilities` by exposing "resolve=local" parameter.
* Fix exposed WFS capabilities to pass cite WFS Simple conformance
* Fixed SORTBY parameter to handle renamed fields.

* Added `GISSERVER_CAPABILITIES_BOUNDING_BOX` setting.
* Added `PropertyIsNull` support (though currently identical to `PropertyIsNil`).
* Fixed `DescribeFeatureType` to return all types when TYPENAMES is not provided.
* Advertise `ImplementsMinimumXPath` in `GetCapabilities` for cite testing (other servers also do this while being incomplete).