Make chests usable if pipeworks is not installed

Rogier

2015-02-07 fcef0ef987f7bd7d26d1c8a4d27a562822b580bc

Make chests usable if pipeworks is not installed

 technic_chests/depends.txt

@@ -1,4 +1,4 @@
default
moreores?
pipeworks
pipeworks?
intllib?

 technic_chests/register.lua

@@ -1,5 +1,22 @@
local S = rawget(_G, "intllib") and intllib.Getter() or function(s) return s end

local pipeworks = rawget(_G, "pipeworks")
if not minetest.get_modpath("pipeworks") then
    -- Pipeworks is not installed. Simulate using a dummy table...
    pipeworks = {}
    local pipeworks_meta = {}
    setmetatable(pipeworks, pipeworks_meta)
    local dummy = function()
        end
    pipeworks_meta.__index = function(table, key)
            print("[technic_chests] WARNING: variable or method '"..key.."' not present in dummy pipeworks table - assuming it is a method...")
            pipeworks[key] = dummy
            return dummy
        end
    pipeworks.after_place = dummy
    pipeworks.after_dig = dummy
end

local chest_mark_colors = {
    {"black", S("Black")},
    {"blue", S("Blue")},