Chef: Gracefully Handle RFC062 Exit Codes

Rename expanders

Match the new names output by the expander nodes

NodePlannableOutput is now the expander node, and is used in contexts
other than planning. Change the name to nodeExpandOutput

NodePLannableLocal is now the expander node, and is is also used in
contexts other than plan. Change the name to nodeExpandLocal.

That name tag was left in only to reduce the diff when during
implementation. Fix the naming now for these nodes so it is correct, and
prevent any possible name collision between types.

Previously the diagnostics from the config loaders (earlyconfig and
regular) were only appended to the overall diags if an error was found.
This adds all diagnostics from the regular config loader so that any
generated warnings will be displayed, even if there are no errors.

I did not add the `earlyconfig` warnings since they will be displayed if
there is an error and are likely to be duplicated by the config loader.

website: Add docs for 0.13upgrade

* internal/registry source: return error if requested provider version protocols are not supported

* getproviders: move responsibility for protocol compatibility checks into the registry client

The original implementation had the providercache checking the provider
metadata for protocol compatibility, but this is only relevant for the
registry source so it made more sense to move the logic into
getproviders.

This also addresses an issue where we were pulling the metadata for
every provider version until we found one that was supported. I've
extended the registry client to unmarshal the protocols in
`ProviderVersions` so we can filter through that list, instead of
pulling each version's metadata.

command: Add prompt & confirmation to 0.13upgrade

internal: Fix LookupLegacyProvider

When looking up the namespace for a legacy provider source, we need to
use the /v1/providers/-/{name}/versions endpoint. For non-HashiCorp
providers, the /v1/providers/-/{name} endpoint returns a 404.

This commit updates the LegacyProviderDefaultNamespace method and the
mock registry servers accordingly.

Validate providers in expanding modules. Expanding modules cannot have provider configurations with non-empty configs, which includes having a version configured. If an empty or alias-only block is passed, the provider must be passed through the providers argument on the module call

[Website] Adding community providers

command: 0.13upgrade command checks and updates required_version

If a configuration had multiple blocks in the versions.tf file, it would
be added to the `rewritePaths` list multiple times. We would then remove
it from this slice, but only once, and so the output file would later be
rewritten to remove the required providers block.

This commit uses a set instead of a list to prevent this case, and adds
a regression test.

Instead of using providers.tf as the default output file for the
upgrader, we now default to versions.tf. This means that if the
configuration has no `required_providers` blocks at all, or has
multiple, the provider version requirements will be stored in the
versions.tf file.

We now also update the versions.tf file to set a `required_version`
attribute in the first `terraform` block, with value ">= 0.13". This
is similar to the behaviour of the 0.12upgrade command, and signals that
the configuration should not be used with older versions of Terraform.

If a configuration has a version constraint which prevents use with
Terraform 0.13, the upgrade command should exit before making any
changes.

Validation is supposed to be a local-only operation, but Configure implementations
are allowed to make outgoing requests to remote APIs to validate settings.

command: Rework 0.13upgrade sub-command

This commit implements most of the intended functionality of the upgrade
command for rewriting configurations.

For a given module, it makes a list of all providers in use. Then it
attempts to detect the source address for providers without an explicit
source.

Once this step is complete, the tool rewrites the relevant configuration
files. This results in a single "required_providers" block for the
module, with a source for each provider.

Any providers for which the source cannot be detected (for example,
unofficial providers) will need a source to be defined by the user. The
tool writes an explanatory comment to the configuration to help with
this.

Add support for force pushing with the remote backend

Both differing serials and lineage protections should be bypassed
with the -force flag (in addition to resources).

Compared to other backends we aren’t just shipping over the state
bytes in a simple payload during the persistence phase of the push
command and the force flag added to the Go TFE client needs to be
specified at that time.

To prevent changing every method signature of PersistState of the
remote client I added an optional interface that provides a hook
to flag the Client as operating in a force push context. Changing
the method signature would be more explicit at the cost of not
being used anywhere else currently or the optional interface pattern
could be applied to the state itself so it could be upgraded to
support PersistState(force bool) only when needed.

Prior to this only the resources of the state were checked for
changes not the lineage or the serial. To bring this in line with
documented behavior noted above those attributes a...

Add more validation to expanding modules

This example doesn't really show how these values should be used. The
default of retry_on_exit_code is now already when most people want, so
this line is not needed in most cases.

I think the docs describe the new options just fine, so lets leave this
out...