~/.xmonad: make windows fullscreen by default

.xmonad/xmonad.hs

(??) :: Query a -> (a -> Bool) -> Query Bool
(??) = flip fmap
myLayout = Full ||| tiled ||| Mirror tiled
    where tiled = Tall nmaster delta ratio
          nmaster = 1
          ratio = 1/2
          delta = 3/100
main = do
    xmonad $ ewmh $ pagerHints $ defaultConfig {
        modMask  = mod4Mask,
                        fullscreenManageHook
                     ] <+> manageHook defaultConfig,
        -- Don't overwrite the section used by docks
        layoutHook = avoidStruts $ smartBorders $ layoutHook defaultConfig,
        layoutHook = avoidStruts $ smartBorders $ myLayout,
        handleEventHook = fullscreenEventHook
     } `additionalKeys` ([
        ((mod4Mask, xK_b), spawnHere "firefox"),