combine NLua with KeraLua (KeraLua is "gone" now I guess)
make it use the BizInvoker (so now it can properly handle the liblua5.4.so and lua54.dll names differing), also delete the liblua54.so.
minor speedup when creating a new empty table
make lua default to UTF8 internally, so we don't need to manually change the state's encoding
339915c013