Update fs2 to 0.10.0-M6
Update fs2 to 0.10.0-M6


http4s/http4s,ChristopherDavenport/http4s,aeons/http4s,ChristopherDavenport/http4s,rossabaker/http4s,aeons/http4s,rossabaker/http4s,reactormonk/http4s,reactormonk/http4s,reactormonk/http4s,ChristopherDavenport/http4s,aeons/http4s