Add support for id ranges to XRC.

Allow to declare ranges of consecutive IDs in XRC by using the "id[n]" syntax.
Show this functionality in the xrc sample and test it in the new unit test.

Also show and test the "object reference" XRC functionality.

Closes #11431.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@66059 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

tests/test_test_gui.dsp

@@ -499,6 +499,10 @@ SOURCE=.\controls\treectrltest.cpp
 
 SOURCE=.\controls\windowtest.cpp
 # End Source File
+# Begin Source File
+
+SOURCE=.\xml\xrctest.cpp
+# End Source File
 # End Group
 # End Target
 # End Project