This includes a bugfix to the cty/msgpack package to ensure correct
decoding of unknown and null values.
This also includes updates to cty's dependencies.
Nomad was manually updated, so revert that to the version in master,
remove it from vendor.json and add it to the ignore list.
Update all packages that were in an unknown state to their latest master
commits.
Previous deps merge had been captured by an older version of godep,
updating godep and rerunning...
godep save $(go list ./... | grep -v /vendor/)
...yielded this diff.
New `godep` also produced a warning to pin to the major Go version
instead of the minor one, which we do here as well.
Martin Atkins