Previously, the spec doesn't update the package status if nothing
in the spec file changed. Due to this, the failed package will
always stay in the failed state.
This PR adds a check to see whether a package is in the failed state.
If yes, then changes the state to pending for builder manager to rebuild it.
This change enables users to have declarative specifications for Fission resources. Users can specify their "app" in a set of spec files, and use a new fission CLI command to "apply" these specs to a running cluster.
The new "spec" CLI also includes archiving of local source files, and a file watcher that re-builds archives and uploads them on file changes, and a package build watcher that waits for package builds on the CLI.
A "--spec" option is also added to "function create", and will be added to other resources in future changes. This option causes a YAML to be outputted to the specs directory instead of the resource being created on the cluster.
The CLI "fission spec --help" outputs usage information.
Minimal golang runtime.
Functions are built as Go plugins, and the plugin is uploaded to fission.
See `environments/go/README.md` for instructions and `examples/go` for a usage example.
For now, we're re-using the 'code' field of the function to store the binary plugin. With v2 environments, this will be stored separately as a binary package.
