This commit ensures that the default interface for the network widget does not update on every render of the bar.
Some people have experienced the bar being frozen and hopefully this will remediate that issue.
This commit adds new settings to some widgets that allows to auto
select/hide them based on their current values.
The cpu/memory/network/storage widgets get a setting that auto selects
the widget if the current value/percentage is over a value.
The battery widget gets a setting that auto selects the widget if the
current percentage is under a value.
The storage widget gets a setting that auto hides the disk widget if the
percentage is under a value.
Also added 2 new settings (auto_select_fill and auto_select_text) to the
theme, in order to select the fill and text colors of an auto selected
widget.
(Easter egg: the network icons change if the value is over the limit)
PR: #1353
