* fixes bug where errors on geometry form were not rendered properly
* fixes bug where invalid geometry was written as read-only back into form (could not be corrected by user)
* adds explanatory comments to SimpleGeomForm is_valid() checks
* reorders code snippets for better understanding
* adds correcting logic to _set_geojson_properties() in case of missing properties element
* fixes bug on netgis map client where importing a geometry would result in an error message
* THIS IS JUST A WORKAROUND AND HAS TO BE REPLACED BY A PROPER FIX FROM THE DEVS ASAP
* adds proper handling in case of BadRequest (error 400)
* enhances html template for error 500
* adds new html template for error 400
* adds uuid_required decorator to missing views
* updates translations
* extends 404 template (user should check the URL)
* introduces new decorator "uuid_required" which performs a check on a given 'uuid' or 'id' parameter
* throws a Http404 exception --> redirect to 404 template instead of 500 error template
* adds bugfixes and improvements
- point / line auto buffer key input change buffer
- pass default buffer values from config
- update area label while vertex editing
- auto buffer remove source geoms when done
- toggle cut tool off when done
- toggle delete tool off when done
- allow panning while vertex editing (middle mouse button)
* adds configurable label-input ratio setting for forms and specializes for RemoveModalForm
* enhances form body html structure for better UX and usage of label-input ratio
* fixes GDALException in case of provided feature (import) without geometry content
* modifies 500.html template to inform the user about the admins being informed automatically
* enhances visualization of editable column on tables
* simplifies code
* enhances visualization of parcel_group column on tables
* WIP: Ordering on intervention table is odd. Same results are being displayed on page 2. Needs further analysis and fixing!
* disables ordering of parcel_group ("Gemarkung") column on tables
* ordering can not be done properly due to more complex nature of this column's content
* introduces "Keine Geometrie vorhanden" message instead of hour glass icon on entries where no geometry has been entered yet
* properly orders last_modified column by moving null values to the lower end of the ordering
