Decoding empty inline table gives wrong result

[shaolang]

Toml.decode!/2 parses the following as %{"a" => %{"b" => 1}}:

a = {}
b = 1

The expected is %{"a" => %{}, "b" => 1}.

This might be related to issue #37. tomerl and TOML libraries from other languages corroborate the expected value.

[jvantuyl]

I think I may have fixed this inadvertently with #41.