#978 Lua script can't access file with unicode path

[the snow]

if file have unicode path,LUA script can not access it.
exp:
lua script saved in J:\drv\驱动源码\test.lua
Content:
print(props["FileDir"])

Error:
cannot open J:\drv\椹卞姩婧愮爜\test.lua: No such file or directory

[Neil Hodgson]

Committed fix.