These changes address the following warning showing up on `go get`
operations:
go: module github.com/golang/protobuf is deprecated: Use the
"google.golang.org/protobuf" module instead.
All changes are made using the recommendations in the per-function
deprecation notices from the docs at
https://pkg.go.dev/github.com/golang/protobuf/ptypes
* Populates ComponentOptions into plugin structs
* Maps options for legacy Provider Plugins into PluginOptions
* Demos use of PluginOptions in a stub provider
* Honors plugin priority and defaultable settings
This uses the new Push plugin support added to the plugin SDK in https://github.com/hashicorp/vagrant-plugin-sdk/pull/106 to make the following changes:
* The plugin manager on the Go side now registers push plugins
* The the _remote_ plugin manager on the Ruby side now calls over to
the go side to get push plugins
* All the wiring is hooked up such that when a push plugin is replaced
with its remote GRPC-client-wielding equivalent, the messages are
ferried around.
Continuing with the error messages audit, this service came out the same
as the basis one - I haven't yet found any tests I can write that
expose errors we would want to enhance. In the meantime, more tests are
good though!
Filling these out as a part of a sweep to ensure we return decent error
messages from our GRPC services.
For this service I didn't come up with any error condition that
warranted changing the code yet. The get -> notfound case seems to be
the main one and the pass through error object seems AOK here.
