crate shelf UX tweaks (#2605)

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## About The Pull Request
changes up description and UI interactions of crate shelves. Mouse
cursor will now switch to a drag+drop cursor when clickdragging crates,
and the description is more descriptive. also changes spans to use the
cleaner span_blahblah() proc
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## Why It's Good For The Game

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## Changelog

🆑 
tweak: cursor will now switch to a clickdrag cursor when clickdragging
crates
tweak: crate shelf description improved
/:cl:

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code/game/objects/structures/crates_lockers/crates.dm

@@ -10,6 +10,7 @@
 	allow_dense = TRUE
 	dense_when_open = TRUE
 	climbable = TRUE
+	mouse_drag_pointer = TRUE
 	climb_time = 10 //real fast, because let's be honest stepping into or onto a crate is easy
 	delivery_icon = "deliverycrate"
 	open_sound = 'sound/machines/crate_open.ogg'

code/game/objects/structures/crateshelf.dm

@@ -15,7 +15,7 @@
 	var/use_delay = DEFAULT_SHELF_USE_DELAY
 	var/list/shelf_contents
 
-/obj/structure/crate_shelf/tall
+/obj/structure/crate_shelf/debug
 	capacity = 12
 
 /obj/structure/crate_shelf/Initialize()
@@ -38,12 +38,12 @@
 
 /obj/structure/crate_shelf/examine(mob/user)
 	. = ..()
-	. += "<span class='notice'>There are some <b>bolts</b> holding [src] together.</span>"
+	. += span_notice("There are some <b>bolts</b> holding [src] together.")
 	if(shelf_contents.Find(null)) // If there's an empty space in the shelf, let the examiner know.
-		. += "<span class='notice'>You could <b>drag</b> a crate into [src]."
+		. += span_notice("You could <b>drag and drop</b> a crate into [src].")
 	if(contents.len) // If there are any crates in the shelf, let the examiner know.
-		. += "<span class='notice'>You could <b>drag</b> a crate out of [src]."
-		. += "<span class='notice'>[src] contains:</span>"
+		. += span_notice("You could <b>drag and drop</b> a crate out of [src].")
+		. += span_notice("[src] contains:")
 		for(var/obj/structure/closet/crate/crate in shelf_contents)
 			. += "	[icon2html(crate, user)] [crate]"
 
@@ -56,13 +56,13 @@
 	return ..()
 
 /obj/structure/crate_shelf/relay_container_resist_act(mob/living/user, obj/structure/closet/crate)
-	to_chat(user, "<span class='notice'>You begin attempting to knock [crate] out of [src].</span>")
+	to_chat(user, span_notice("You begin attempting to knock [crate] out of [src]"))
 	if(do_after(user, 30 SECONDS, target = crate))
 		if(!user || user.stat != CONSCIOUS || user.loc != crate || crate.loc != src)
 			return // If the user is in a strange condition, return early.
-		visible_message("<span class='warning'>[crate] falls off of [src]!</span>",
-						"<span class='notice'>You manage to knock [crate] free of [src].</span>",
-						"<span class='notice>You hear a thud.</span>")
+		visible_message(span_warning("[crate] falls off of [src]!"),
+						span_notice("You manage to knock [crate] free of [src]"),
+						span_notice("You hear a thud."))
 		crate.forceMove(drop_location()) // Drop the crate onto the shelf,
 		step_rand(crate, 1) // Then try to push it somewhere.
 		crate.layer = initial(crate.layer) // Reset the crate back to having the default layer, otherwise we might get strange interactions.
@@ -125,12 +125,12 @@
 			if(1) // Believe it or not, this does nothing.
 			if(2) // Open the crate!
 				if(crate.open()) // Break some open, cause a little chaos.
-					crate.visible_message("<span class='warning'>[crate]'s lid falls open!</span>")
+					crate.visible_message(span_warning("[crate]'s lid falls open!"))
 				else // If we somehow fail to open the crate, just break it instead!
-					crate.visible_message("<span class='warning'>[crate] falls apart!")
+					crate.visible_message(span_warning("[crate] falls apart!"))
 					crate.deconstruct()
 			if(3) // Break that crate!
-				crate.visible_message("<span class='warning'>[crate] falls apart!")
+				crate.visible_message(span_warning("[crate] falls apart!"))
 				crate.deconstruct()
 		shelf_contents[shelf_contents.Find(crate)] = null
 	if(!(flags_1&NODECONSTRUCT_1))