ResultVectorLayer - singleMode and singleResource

[adube]

In the ResultVectorLayer widget, have :

• a new 'singleResource' Private property. String. Automatically set by the 'singleMode' option upon adding features to the layer. See below.
• a new 'singleMode' API property (option). Boolean. Defaults to false. When set to true, the first valid feature to be added to the layer that has is linked to a resource will set the 'singleResource' property equal to the feature's resource. From there on, only features of this specific resource will be added.
• when 'singleResource' is set, set the query widget 'multiQueryResource' as well.
• when reseting the results, if query was not in 'multiple' mode, reset the 'singleResource' and 'multiQueryResource' properties. Requires #212.

[adube]

#212 : a small change of task will be required. Instead of "Letting the results know when QueryOnClick widget was in 'multiple' mode. " when querying, it should be when reseting instead (before querying).

[adube]

r1024, featuring :

• all the above features in the description above
• documentation about new 'singleMode' option
• queryonclick/mutli example updated to use 'singleMode'
• small bug fix in getObjectFromNode call in xslt file to get the widget options.

Done.