This work was done against APIs that were already changed in the branch
before work began, and so it doesn't apply to the v0.12 development work.
To allow v0.12 to merge down to master, we'll revert this work out for now
and then re-introduce equivalent functionality in later commits that works
against the new APIs.
In TFE you can configure a workspace to use a custom working directory. When determining which directory that needs to be uploaded to TFE, this working directory should be taken into account to make sure we are uploading the correct root directory for the workspace.