Update Battery widget plugin (#201)

* fix: setUpdateInterval in update function

* fix: add shellEscape on cat command

* dump version

* fix: migrate settings to desktop_widget.settings

* feat: auto gap based on the layout

* feat: retrieve warning threshold from noctalia's settings

battery-widget/README.md

@@ -11,7 +11,7 @@ Desktop/lockscreen widget that displays the current battery level and charging s
 
 ## Usage
 
-Add it to your desktop/lockscreen widgets.
+Add it to your desktop/lockscreen widgets using the widget editor. You can configure it in the widget settings.
 
 ## Settings
 
@@ -23,7 +23,7 @@ Add it to your desktop/lockscreen widgets.
 | `hide_plugged` | `bool` | `false` | Hide the battery widget when connected to AC power. |
 | `hide_full` | `bool` | `false` | Hide the battery widget when fully charged. |
 | `color` | `color` | `on_surface` | Color role for this widget's icon and label; fixed hex colors are also supported. |
-| `warning_color` | `color` | `error` | Color applied when charge is at or below 20%. |
+| `warning_color` | `color` | `error` | Color applied when charge is at or below warning threshold. |
 | `charging_color` | `color` | `on_surface` | Color applied when connected to AC power. |
 | `battery` | `select` | `auto` | Detect the battery automatically or set a custom name. |
 | `battery_name` | `string` | `BAT0` | Set a custom name for the battery. |
@@ -32,3 +32,4 @@ Add it to your desktop/lockscreen widgets.
 ## Notes
 
 `hide_full` and `hide_plugged` do not hide the background due to plugin limitations.
+The warning threshold is pulled from noctalia's settings.