Implement component bootstrapping

[ionut-arm]

The service now offers operations that can be used to bootstrap the client library into using the recommended provider and the supported authentication method.

Currently the users of BasicClient need to make those calls themselves and then configure the client object, but there's no reason that functionality cannot be implemented on top of or into BasicClient to limit code duplication.

A design proposal should be made before this can be started.

[hug-dev]

In the BasicClient we would add two methods:

• set_default_provider: will set the first provider returned by ListProviders
• set_default_auth_data: will set the appropriate auth data based on the first auth type returned by ListAuthenticators

In the new constructor: set the two defaults.

[ionut-arm]

Do you think we should have new set the defaults or should we leave it as is and only call the default methods in Default::default()?

[ionut-arm]

It's a bit annoying that there's no method overloading in Rust... :( would've been nice to have one new with an AppIdentity param and one without.

[hug-dev]

Maybe there could be different kind of constructions:

• new with no paramaters choosing everything for you
• new_with_auth_data: setting only the auth data
• etc...

Implementing Default might be hard on types if you don't have access to a client to call ListProviders or ListAuthenticators?

[ionut-arm]

Implementing Default might be hard on types if you don't have access to a client to call ListProviders or ListAuthenticators?

? I think you can just create a client, call the methods on it and return it. That's what new will do as well.

[ionut-arm]

Done in #58