Use saner window swapping defaults.

.config/awesome/rc.lua

@@ -238,13 +238,13 @@ globalkeys = gears.table.join(
     awful.key({ modkey,           }, "Escape", awful.tag.history.restore,
               {description = "go back", group = "tag"}),
 
-    awful.key({ modkey,           }, "j",
+    awful.key({ "Mod1",           }, "Tab",
        function ()
 	  awful.client.focus.byidx( 1)
        end,
        {description = "focus next by index", group = "client"}
     ),
-    awful.key({ modkey,           }, "k",
+    awful.key({ "Mod1", "Shift"   }, "Tab",
        function ()
 	  awful.client.focus.byidx(-1)
        end,
@@ -264,7 +264,7 @@ globalkeys = gears.table.join(
        {description = "focus the previous screen", group = "screen"}),
     awful.key({ modkey,           }, "u", awful.client.urgent.jumpto,
        {description = "jump to urgent client", group = "client"}),
-    awful.key({ modkey,           }, "Tab",
+    awful.key({ modkey,           }, "j",
        function ()
 	  awful.client.focus.history.previous()
 	  if client.focus then