OpenOS: /lib/package.lua: add support for preload and config (#3447)

Add basic implementations of package.preload and package.config,
necessary to get the Fennel compiler ( https://fennel-lang.org )
running.

src/main/resources/assets/opencomputers/loot/openos/lib/package.lua

@@ -1,9 +1,13 @@
 local package = {}
 
+package.config = "/\n;\n?\n!\n-\n"
+
 package.path = "/lib/?.lua;/usr/lib/?.lua;/home/lib/?.lua;./?.lua;/lib/?/init.lua;/usr/lib/?/init.lua;/home/lib/?/init.lua;./?/init.lua"
 
 local loading = {}
 
+local preload = {}
+
 local loaded = {
  ["_G"] = _G,
  ["bit32"] = bit32,
@@ -15,6 +19,7 @@ local loaded = {
  ["table"] = table
 }
 package.loaded = loaded
+package.preload = preload
 
 function package.searchpath(name, path, sep, rep)
  checkArg(1, name, "string")
@@ -46,6 +51,14 @@ function require(module)
  checkArg(1, module, "string")
  if loaded[module] ~= nil then
  return loaded[module]
+ elseif package.preload[module] then
+ assert(type(package.preload[module]) == "function", string.format("package.preload for '%s' is not a function", module))
+ loading[module] = true
+ local library, status = pcall(package.preload[module], module)
+ loading[module] = false
+ assert(library, string.format("module '%s' load failed:\n%s", module, status))
+ loaded[module] = status
+ return status
  elseif not loading[module] then
  local library, status, step