add minimum minetest version key for contentdb

Prevent the node breaker from digging all nodes

See merge request VanessaE/pipeworks!19

mod.conf

@@ -2,3 +2,4 @@ name = pipeworks
 description = This mod uses mesh nodes and nodeboxes to supply a complete set of 3D pipes and tubes, along with devices that work with them.
 depends = default, basic_materials, screwdriver
 optional_depends = mesecons, mesecons_mvps, digilines, signs_lib
+min_minetest_version = 5.2.0

signal_tubes.lua

@@ -80,7 +80,7 @@ if digiline_enabled and pipeworks.enable_digiline_detector_tube then
 
 						local setchan = meta:get_string("channel")
 
-						digiline:receptor_send(pos, digiline.rules.default, setchan, stack:to_string())
+						digiline:receptor_send(pos, digiline.rules.default, setchan, stack:to_table())
 
 						return pipeworks.notvel(pipeworks.meseadjlist, velocity)
 					end},

tube_registration.lua

@@ -58,7 +58,7 @@ local register_one_tube = function(name, tname, dropname, desc, plain, noctrs, e
 
 	local tgroups = {snappy = 3, tube = 1, tubedevice = 1, not_in_creative_inventory = 1}
 	local tubedesc = string.format("%s %s", desc, dump(connects))
-	local iimg = plain[1]
+	local iimg = type(plain[1]) == "table" and plain[1].name or plain[1]
 	local wscale = {x = 1, y = 1, z = 1}
 
 	if #connects == 0 then

wielder.lua

@@ -40,7 +40,7 @@ local can_tool_dig_node = function(nodename, toolcaps, toolname)
 		-- but a player holding one can - the game seems to fall back to the hand.
 		-- fall back to checking the hand's properties if the tool isn't the correct one.
 		local hand_caps = minetest.registered_items[""].tool_capabilities
-		diggable = minetest.get_dig_params(nodegroups, hand_caps)
+		diggable = minetest.get_dig_params(nodegroups, hand_caps).diggable
 	end
 	return diggable
 end