Feature/Add search command

[Blokje5]

The search command allows the policy-hub-cli to search through a registry. It expects a path to a registry file containing the metadata + a search query. Then it constructs a bleve.Index if it did not exist, indexes the metadata and performs the search query.

The end result looks like this:

It is a bit of a prototype, so it definitely is not perfect. There are a few improvements we still need to do:

• Structure the output, I just used the default bleve output
• The code can probably be cleaned a bit, tests can be added as well
• Ideally it works for multiple registries, right now I just index one

but it is a starting point

[xchapter7x]

Nice. I like it.
As we get a clearer view as to the UX and desired behaviors we can begin to add tests and things.

This is a great starting point to start designing the command set and user interactions.

👍