incorrect usage of types in function selectors

[InoMurko]

Based on:
https://github.com/poanetwork/ex_abi/blob/master/lib/abi/type_decoder.ex#L140
and
https://github.com/poanetwork/ex_abi/blob/master/lib/abi/function_selector.ex#L29

a function selector return types get completely ignored - so even basic function return data doesn't get parsed.
For example:

selector = %ABI.FunctionSelector{
  function: "getVersion",
  input_names: [],
  inputs_indexed: nil,
  method_id: <<13, 142, 110, 44>>,
  returns: [:string],
  type: :function,
  types: []
}

was parsed directly from our solidity contract abi (json):

abi_path
      |> File.read!()
      |> Jason.decode!()
      |> Map.fetch!("abi")
      |> ABI.parse_specification(include_events?: true)

data2 = method_id |> Encoding.to_hex() |> Kernel.<>(data) |> Encoding.from_hex 
ABI.find_and_decode([selector], data2)

where

iex(196)> method_id
<<13, 142, 110, 44>>
iex(197)> data
"0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000d312e302e342b6136396337363300000000000000000000000000000000000000"
iex(198)>

and returns this:

{%ABI.FunctionSelector{
   function: "getVersion",
   input_names: [],
   inputs_indexed: nil,
   method_id: <<13, 142, 110, 44>>,
   returns: [:string],
   type: :function,
   types: []
 }, []}

if we modify the selector to (returns and types were swaped):

selector = %ABI.FunctionSelector{
  function: "getVersion",
  input_names: [],
  inputs_indexed: nil,
  method_id: <<13, 142, 110, 44>>,
  returns: [],
  type: :function,
  types: [:string],
}
ABI.find_and_decode([selector], data2)
{%ABI.FunctionSelector{
   function: "getVersion",
   input_names: [],
   inputs_indexed: nil,
   method_id: <<13, 142, 110, 44>>,
   returns: [],
   type: :function,
   types: [:string]
 }, ["1.0.4+a69c763"]}