This basically removes the "adv" library, even though it's still
preserved for compatibility with user make/project files referring to
it.
It is done because the distinction between "adv" and "core" was never
really clear (e.g. why wxTreeCtrl was in core but wxTreeListCtrl in
adv?) and it prevented some core classes from using adv ones.
Standardize on using sample.rc and sample icon in all the samples, it was
confusing that some of them used it and other didn't, without any apparent
logic.
Remove the now unnecessary icon files, including the dialogs sample icon which
seemed to be corrupted (this closes#11146).
Also replace multiple OS/2 resource files with a single one in the sample
directory. The OS/2 projects/makefiles would need to be updated to use them.
Remove dialogs sample icon.
git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@64645 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775