QueryByRect - new widget

[adube]

Have a new widget that generates queries by drawing rectangles on the map.

The features should be exactly the same as the QueryOnClick widget, except that the queries will be made on featureserver services rather than wms and by drawing a rectangle instead of clicking on the map.

Only visible layers generates an according featureserver query.

Notice

Since the delay for this widget is quite short, it was designed that way but should be deprecated in the near future by a new and better widget derived from OpenLayers library.

[adube]

r958, featuring the new QueryByRect widget.

This commit was made in Borealis branch. I'll soon apply the same patch to trunk also and will give more technical details then.

[adube]

r959, featuring :

• new QueryByRect widget that makes GetFeature requests using the HTTP protocol with a BBOX filter (rectangle) drawn on the map by the user.
• documentation
• sample
• i18n
• a fix in the ResultExtGrid widget : grids and records are now classified by resource instead of WMS 'type'
• a temp fix in the InitialView widget (call to an non-existant method ?)

More details

• Even though this widget is fully functional, it was developed to quickly demonstrate the "query by rect" feature and should be replaced in the mid future by the OpenLayers.Control.GetFeature control instead.
• Not supported by the PGSQLMapContextConfig driver, but that wouldn't be too hard to accomplish. If anyone wishes it, please create the according ticket.

Task done.