v0.4.1

• improve labels for wms-layer-filter
• bugfix: timecontrol is missing on first page load
• add validation for WMS-Legends to check that color-limits are in the correct order
• assign area in layer-forms again, because inline-formset in area-form could get too large (page crashes when having >200 layers rendered with 3 fk-fields)
• add validation to legend-name to prevent error in GeoServer-API-Request