Pin utfbom and go-homedir to v1.0.0 and remove the explicit dependency on x/crypto master

[ultimateboy]

I ran into some issues today with a build pipeline that has this project as a dependency. Some changes to x/crypto weren't valid with some of my other dependencies, and the explicit pinning to master here causes pain upstream (having to use dep overrides). I don't see any reason why go-autorest needs to always be pinned to master, so I've removed this - dep will use the most recent valid version it can.

While I was at it, I also added specific versions (v1.0.0) for utfbom and go-homedir.

None of these changes actually change the dependencies in any way, as seen with the simple diff on the Gopkg.lock file. This just helps other repos which import this project.

As for checking the boxes that this is an "urgent bug fix" and warrants its own release, that's up to you - I altered the changelog in a separate commit. But given this is dealing with how projects import go-autorest, I think it would be prudent to tag a patch release with these changes.

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[jhendrixMSFT]

Sorry for the delay on this, I've rolled your changes into #326.