Create a tool to convert v1alpha1 configs to v1alpha2 configs to make v1alpha1 deprecation less painful.

Considerations:

1. For convenience only. Should be able to handle the majority of configs, but not all edge cases. The tool should warn the user in these cases ideally.
2. Not all sets of v1alpha1 config can be converted perfectly. Warn when this happens.
3. Output should just be a starting point for the v1alpha3 configs. Users will probably want to clean up and rename generated names etc.

Part of #1925