fix stream api: don't use the process dictionary here

Author: zookzook

lib/mongo/stream.ex

@@ -38,7 +38,6 @@ defmodule Mongo.Stream do
     case Mongo.get_session(opts) do
       nil ->
         with {:ok, session} <- Session.start_session(topology_pid, :read, opts) do
-          Process.put(:session, session)
           {:own, session}
         end
 
@@ -49,7 +48,6 @@ defmodule Mongo.Stream do
 
   def checkin_session(:own, session, topology_pid) do
     Session.end_session(topology_pid, session)
-    Process.delete(:session)
   end
 
   def checkin_session(:borrowed, _session, _topology_pid) do

mix.exs

@@ -2,7 +2,7 @@ defmodule Mongodb.Mixfile do
   use Mix.Project
 
   @source_url "https://github.com/zookzook/elixir-mongodb-driver"
-  @version "0.9.0-rc.0"
+  @version "0.9.0-rc.1"
 
   def project() do
     [