feat: support swallow in window rule

config.conf

@@ -99,6 +99,8 @@ tags=id:9,layout_name:tile
 # monitor  : type-int(0-99999)
 # width : type-num(0-9999)
 # height : type-num(0-9999)
+# isterm : type-num (0 or 1) -- when new window open, will replace it, and will restore after the sub window exit
+# nnoswallow : type-num(0 or 1) -- if enable, this window wll not replace isterm window when it was open by isterm window
 
 # example
 # windowrule=isfloating:1,appid:yesplaymusic