In the past, we had a mode where the CLI would upload the Pulumi
program, as well as its contents and do the execution remotely.
We've since stopped supporting that, but all the supporting code has
been left in the CLI.
This change removes the code we had to support the above case,
including the `pulumi archive` command, which was a debugging tool to
generate the archive we would have uploaded (which was helpful in the
past to understand why behavior differed between local execution and
remote execution.)
74672857fd