Remove temporary description string, add assert to force description field to be present in rail definitions and fix descriptions for on variants of rail

mods/ENTITIES/mcl_minecarts/rails.lua

@@ -122,7 +122,6 @@ local BASE_DEF = {
 		dig_by_water=0,destroy_by_lava_flow=0,
 		transport=1
 	},
-	description = S("New Rail"), -- Temporary name to make debugging easier
 	_tt_help = S("Track for minecarts"),
 	_doc_items_usagehelp = railuse,
 	_doc_items_longdesc = S("Rails can be used to build transport tracks for minecarts. Normal rails slightly slow down minecarts due to friction."),
@@ -186,6 +185,7 @@ table_merge(SLOPED_RAIL_DEF,{
 
 function mod.register_rail(itemstring, ndef)
 	assert(ndef.tiles)
+	assert(ndef.description)
 
 	-- Extract out the craft recipe
 	local craft = ndef.craft

mods/ENTITIES/mcl_minecarts/rails/activator.lua

@@ -51,6 +51,7 @@ mod.register_curves_rail("mcl_minecarts:activator_rail_v2_on", {
 	"mcl_minecarts_rail_activator_t_junction_powered.png",
 	"mcl_minecarts_rail_activator_crossing_powered.png"
 },{
+	description = S("Activator Rail"),
 	_doc_items_create_entry = false,
 	groups = {
 		not_in_creative_inventory = 1,

mods/ENTITIES/mcl_minecarts/rails/detector.lua

@@ -48,6 +48,7 @@ mod.register_curves_rail("mcl_minecarts:detector_rail_v2_on",{
 	"mcl_minecarts_rail_detector_t_junction_powered.png",
 	"mcl_minecarts_rail_detector_crossing_powered.png"
 },{
+	description = S("Detector Rail"),
 	groups = {
 		not_in_creative_inventory = 1,
 	},

mods/ENTITIES/mcl_minecarts/rails/powered.lua

@@ -46,6 +46,7 @@ mod.register_curves_rail("mcl_minecarts:golden_rail_v2_on",{
 	"mcl_minecarts_rail_golden_t_junction_powered.png",
 	"mcl_minecarts_rail_golden_crossing_powered.png",
 },{
+	description = S("Powered Rail"),
 	_doc_items_create_entry = false,
 	_rail_acceleration = function(pos, staticdata)
 		if staticdata.velocity ~= 0 then