waybar: add page (#12872)

Co-authored-by: Lena <126529524+acuteenvy@users.noreply.github.com>
Co-authored-by: spageektti <git@spageektti.cc>

pages/common/waybar.md

@@ -0,0 +1,20 @@
+# waybar
+
+> Highly customizable Wayland bar for Sway and Wlroots based compositors.
+> More information: <https://github.com/Alexays/Waybar>.
+
+- Start `waybar` with the default configuration and stylesheet:
+
+`waybar`
+
+- Use a different configuration file:
+
+`waybar {{-c|--config}} {{path/to/config.jsonc}}`
+
+- Use a different stylesheet file:
+
+`waybar {{-s|--style}} {{path/to/stylesheet.css}}`
+
+- Set the logging level:
+
+`waybar {{-l|--log-level}} {{trace|debug|info|warning|error|critical|off}}`