remove lang strings

public/language/en-GB/user.json

@@ -130,9 +130,6 @@
 	"enable_topic_searching": "Enable In-Topic Searching",
 	"topic_search_help": "If enabled, in-topic searching will override the browser's default page search behaviour and allow you to search through the entire topic, instead of what is only shown on screen",
 
-	"delay_image_loading": "Delay Image Loading",
-	"image_load_delay_help": "If enabled, images in topics will not load until they are scrolled into view",
-
 	"scroll_to_my_post": "After posting a reply, show the new post",
 
 	"follow_topics_you_reply_to": "Watch topics that you reply to",