I have been using Gtk2::GladeXML::Simple for some time, and while
Gtk2::Builder is somewhat less work to use than Gtk2::GladeXML, I got
used to Gtk2::GladeXML::Simple and its widget access via
$self->{widget}. Since Glade3-3.6.0 was released and seems to be a
lot more stable than the 3.5.x series, and supports GtkBuilder, I
decided to start switching to Gtk2::Builder, but did not see anything
like Gtk2::GladeXML::Simple. Thus I modified Gtk2::GladeXML::Simple
to be similar but with Gtk2::Builder support.