Add various factoids and complete some food help

mods/HELP/mcl_doc/depends.txt

@@ -1 +1,2 @@
+doc
 doc_items

mods/HELP/mcl_doc/init.lua

@@ -8,3 +8,71 @@ minetest.register_on_player_receive_fields(function(player, formname, fields)
 		doc.show_doc(player:get_player_name())
 	end
 end)
+
+-- doc_items factoids
+
+-- dig_by_water
+doc.sub.items.register_factoid("nodes", "drop_destroy", function(itemstring, def)
+	if def.groups.dig_by_water then
+		return "Water can flow into this block and cause it to drop as an item."
+	end
+	return ""
+end)
+
+-- usable by hoes
+doc.sub.items.register_factoid("nodes", "groups", function(itemstring, def)
+	if def.groups.cultivatable == 2 then
+		return "This block can be turned into dirt with a hoe."
+	elseif def.groups.cultivatable == 2 then
+		return "This block can be turned into farmland with a hoe."
+	end
+	return ""
+end)
+
+-- soil
+doc.sub.items.register_factoid("nodes", "groups", function(itemstring, def)
+	local datastring = ""
+	if def.groups.soil_sapling == 2 then
+		datastring = datastring .. "This block acts as a soil for all saplings." .. "\n"
+	elseif def.groups.soil_sapling == 1 then
+		datastring = datastring .. "This block acts as a soil for some saplings." .. "\n"
+	end
+	if def.groups.soil_sugarcane then
+		datastring = datastring .. "Sugar canes will grow on this block." .. "\n"
+	end
+	if def.groups.soil_nether_wart then
+		datastring = datastring .. "Nether wart will grow on this block." .. "\n"
+	end
+	return datastring
+end)
+
+-- flammable
+doc.sub.items.register_factoid("nodes", "groups", function(itemstring, def)
+	if def.groups.flammable then
+		return "This block is flammable."
+	end
+	return ""
+end)
+
+-- destroys_items
+doc.sub.items.register_factoid("nodes", "groups", function(itemstring, def)
+	if def.groups.destroys_items then
+		return "This block destroys any item it touches."
+	end
+	return ""
+end)
+
+
+-- Comestibles
+doc.sub.items.register_factoid(nil, "use", function(itemstring, def)
+	if def.groups.eatable and not def._doc_items_usagehelp then
+		if def.groups.food == 2 then
+			return "To eat it, wield it, then rightclick."
+		elseif def.groups.food == 3 then
+			return "To drink it, wield it, then rightclick."
+		else
+			return "To consume it, wield it, then rightclick."
+		end
+	end
+	return ""
+end)