Add new window switcher on super+tab and smaller fixes

awesome/src/tools/helpers/gpu_usage.lua

@@ -0,0 +1,11 @@
+local awful = require("awful")
+local watch = awful.widget.watch
+
+watch(
+  [[ bash -c "nvidia-smi -q -d UTILIZATION | grep Gpu | awk '{print $3}'"]],
+  3,
+  function(_, stdout)
+    stdout = stdout:match("%d+")
+    awesome.emit_signal("update::gpu_usage", stdout)
+  end
+)