it is a widely accepted rule to shape names with the usage site in mind.
Especially this means, that we use the singular form for all kinds
of collections and assortments.
Thus, the namespace should be called "widget" not "widgets",
because at usage site this becomes gui::widget::TimelineWidget
Likewise for "dialogs" and "pannels"
Lots off commented out blocks of code
but most issues are related to simple function name changes,
set/get_flags calls, anything that has to do with a Gtk::Style...
Plan of attack from here is to go one-by one of each commented-out or code and update to gtk3 specs.
