try .pbc before .lua

tests run faster because Test.More is already compiled.
Now, with previous commit, require 'Test.More' loads
 languages/lua/library/Test/More.pbc
instead of
 library/Test/More.pbc

src/lib/luapackage.pir

@@ -52,14 +52,14 @@ LIST
     set $P2, 1
     _loaders[$P2] = loader_preload
 
-    .const 'Sub' loader_Lua = 'loader_Lua'
-    inc $P2
-    _loaders[$P2] = loader_Lua
-
     .const 'Sub' loader_PBC = 'loader_PBC'
     inc $P2
     _loaders[$P2] = loader_PBC
 
+    .const 'Sub' loader_Lua = 'loader_Lua'
+    inc $P2
+    _loaders[$P2] = loader_Lua
+
     .const 'Sub' loader_PBCroot = 'loader_PBCroot'
     inc $P2
     _loaders[$P2] = loader_PBCroot