Implement export of item icons and locale

Add mod and command for exporting the Factorio locale including mods,
and item icons assemled into a sprite sheet including mods.

lua/export/data-final-fixes.lua

@@ -0,0 +1,101 @@
+local item_types = {
+    -- Item categories
+    "item",
+    "ammo",
+    "capsule",
+    "gun",
+    "item-with-entity-data",
+    "item-with-label",
+    "item-with-inventory",
+    "blueprint-book",
+    "item-with-tags",
+    "selection-tool",
+    "blueprint",
+    "deconstruction-item",
+    "copy-paste-tool",
+    "upgrade-item",
+    "module",
+    "rail-planner",
+    "tool",
+    "armor",
+    "mining-tool",
+    "repair-tool",
+
+    -- Fluids
+    "fluid",
+}
+
+local function is_array(t)
+    local count = 0
+    for k in pairs(t) do
+        if type(k) ~= "number" then
+            return false
+        end
+        count = count + 1
+    end
+
+    for i = 1, count do
+        if not t[i] then
+            return false
+        end
+    end
+
+    return count ~= 0
+end
+
+-- no game.table_to_json here :(
+local function table_to_json(data)
+    if type(data) == "number" then
+        return string.format("%.17g", data)
+
+    elseif type(data) == "string" then
+        data = data:gsub('([\x00-\x1f\\"])', function(match)
+            return "\\x" .. string.format("%02x", match:byte())
+        end)
+        return '"' .. data .. '"'
+
+    elseif data == nil then
+        return "null"
+
+    elseif data == true then
+        return "true"
+    elseif data == false then
+        return "false"
+
+    elseif type(data) == "table" then
+        local r
+        if is_array(data) then
+            r = {"["}
+            for i=1, #data do
+                r[#r+1] = table_to_json(data[i])
+                r[#r+1] = ","
+            end
+
+            -- overwrite last comma, empty table is an object
+            r[#r] = "]"
+
+        else
+            r = {"{"}
+            for k, v in pairs(data) do
+                r[#r+1] = table_to_json(tostring(k))
+                r[#r+1] = ":"
+                r[#r+1] = table_to_json(v)
+                r[#r+1] = ","
+            end
+            r[#r + (r[#r] == "," and 0 or 1)] = "}"
+        end
+
+        return table.concat(r)
+    end
+end
+
+local function send_json(channel, data)
+    data = table_to_json(data)
+    print("\f$ipc:" .. channel .. "?j" .. data)
+end
+
+for _, group in ipairs(item_types) do
+    for _, item in pairs(data.raw[group]) do
+        send_json("item_export", item)
+    end
+end