Bump patch version to silence Elixir 1.4 warnings

While `mix test` seems to work just fine using Elixir 1.4, it spits out
a bunch of warnings for zero-arity function calls (cf.
elixir-lang/elixir#3268).

This was fixed by #2. Those changes are still compatible with Elixir
1.3, so no need for a major version bump. But Elixir 1.4 users probably
don't appreciate all these warnings.

mix.exs

@@ -3,7 +3,7 @@ defmodule RemoteIp.Mixfile do
 
   def project do
     [app: :remote_ip,
-     version: "0.1.2",
+     version: "0.1.3",
      elixir: "~> 1.3",
      package: package(),
      description: description(),