Access to svg id from the Drawable class

Following quick and dirty patch provide access to svg-element ‘id’ property from Drawable::getName method.

Accessing to id property allows the code to perform named picking/hit on a drawable tree, which sounds very usefull !

Hope it will get included :slight_smile:

Accessing to id property will also allows to perform some selective interactive rendering of a svg based drawable !

Ok, seems like a sensible thing to add!