Fix for assertion failure when displaying Add Property dialog on Linux

Assertion was "../src/gtk/dataview.cpp(3639): assert "parent_node" failed in
ItemAdded(): Did you forget a call to ItemAdded()? The parent node is unknown
to the wxGtkTreeModel"

I could find no logical reason for this error since ItemAdded() certainly WAS
being called for the parent item, however switching to the built-in
wxTreeListCtrl fixes the problem (at the expense of losing certain advanced
functionality like rich text formatting).
Merge remote-tracking branch 'codereader/master'
Updated debian changelog
Updated Linux build version number
Merge remote-tracking branch 'codereader/master'

Integrate TreeModel fix on Linux.
Revert AddPropertyDialog changes made obsolete by TreeModel fix

This reverts commit 2a553a5798cef65f01440406a58a4bc9bb4855d0.