We're providing a local test server for the consul backends, so we might
as well use it to make the provider acceptance tests more relible as
well.
TODO: the TLS test doesn't actualy test anything other than the Config.
The tests have been modified to make it apparent that they aren't
connecting to the server at all.
Previously the consul_keys resource did double-duty as both a reader and
writer of values from the Consul key/value store, but that made its
interface rather confusing and complex, as well as having all of the other
general problems associated with read-only resources.
Here we split the functionality such that reading is done with the
consul_keys data source while writing is done with the consul_keys
resource.
The old read behavior of the resource is still supported, but it's no
longer documented (except as a deprecation note) and will generate
deprecation warnings when used.
In future it should be possible to simplify the consul_keys resource by
removing all of the read support, but that is deferred for now to give
users a chance to gracefully migrate to the new data source.