def add_as_lowest(var, value)
      # Don't want to override anything, so just shift in a dummy site config at the lowest level and
      # set the value there.
      configs.append(Config.new(path: :runtime, parent: self, values: { var.to_s => value }))
    end
def add_as_lowest(var, value)
      # Don't want to override anything, so just shift in a dummy site config at the lowest level and
      # set the value there.
      configs.append(Config.new(path: :runtime, parent: self, values: { var.to_s => value }))
    end
Dynamically add a new site variable at the lowest priority.
 Essentially, this sets a new default value.