Add CheckRedirect for GO 1.8

[dnephin]

We need to make sure that we get the fix from moby/moby#32127 if we want to build the client with GO 1.8.

The changes in that PR will not affect the cli because a client is created in cli/command/cli.go, so we need to use the CheckRedirect function from that PR where we create the client.

[dnephin]

The referenced PR was merged so we can now make this change.

[boaz0]

@dnephin does that make sense if I call #dibs on that?

[dnephin]

That would be great, thank you!

[boaz0]

@dnephin it seems like moby/moby#32127 was added in #45 so I think we can close this.

I built this on my computer and CheckRedirect works.

[dnephin]

This repo doesn't use the code from moby/moby to create an http.Client. I'll open a PR, it should be small.