Also latest Elixir

Author: josevalim

.travis.yml

@@ -4,7 +4,6 @@ elixir:
   - 1.9
   - 1.8
   - 1.7
-  - 1.6
 otp_release:
   - 20.0
   - 21.0

lib/bypass/plug.ex

@@ -18,7 +18,7 @@ defmodule Bypass.Plug do
             conn
         catch
           class, reason ->
-            stacktrace = System.stacktrace()
+            stacktrace = __STACKTRACE__
             put_result(pid, route, ref, {:exit, {class, reason, stacktrace}})
             :erlang.raise(class, reason, stacktrace)
         end

mix.exs

@@ -8,7 +8,7 @@ defmodule Bypass.Mixfile do
     [
       app: :bypass,
       version: @version,
-      elixir: "~> 1.6",
+      elixir: "~> 1.7",
       description: description(),
       package: package(),
       deps: deps(),