add Lua sandbox with timer system (milestones 1-5 complete)

sandbox-test/scripts/test_string_dump_removed.lua

@@ -0,0 +1,18 @@
+-- Test that string.dump is removed
+-- string.dump can be used to create bytecode from functions,
+-- which could be used to bypass sandbox restrictions
+
+if string.dump ~= nil then
+    error("FAIL: string.dump should be nil but exists")
+end
+
+-- Also verify string table exists and other functions work
+if string.upper == nil then
+    error("FAIL: string.upper should exist")
+end
+
+if string.format == nil then
+    error("FAIL: string.format should exist")
+end
+
+print("PASS: string.dump removed, other string functions intact")