Update to Awesome 4.0

Configuration works mostly identical to previous state. Some exceptions:
- Minor changes in tag names (removed unicode symbols), as they are now
  referenced by name in the rules.
- Calendar module is not yet ported and not loaded.
- Scratch terminal on F12 key currently moves to bottom of the screen after
  first opening. Probably will be reimplemented using the new extended
  awful.spawn API.
- awsetbg util writes different wallpaperrc (preexisting wallpaperrc is ignored,
  as the filename now includes .lua)

awsetbg

@@ -1,6 +1,6 @@
 #!/bin/zsh
 
-WALLPAPERRC=$(awesome-client <<<'return awful.util.getdir("config") .. "/wallpaperrc"' | sed -e 's/.*string "\(.*\)"/\1/')
+WALLPAPERRC=$(awesome-client <<<'return require("awful").util.getdir("config") .. "/wallpaperrc.lua"' | sed -e 's/.*string "\(.*\)"/\1/')
 
 mode="-f"
 
@@ -73,12 +73,13 @@ require('gears').wallpaper.${method}(\"${wall}\",s${extra_args})
 end" | awesome-client
 
 if [[ -n "$update" ]]; then
-	echo "-- wallpaperrc generated by awsetbg
+echo "-- wallpaperrc generated by awsetbg
+gears = require(\"gears\")
+function set_wallpaper(s)
 	local wall=\"${wall}\"
 	local f = io.open(wall, \"r\")
 	if f~= nil then
-		for s = 1, screen.count() do
-			require('gears').wallpaper.${method}(wall,s${extra_args})
-		end
-	end" > $WALLPAPERRC
+		gears.wallpaper.${method}(wall,s${extra_args})
+	end
+end" > $WALLPAPERRC
 fi