Update cursive-core to 0.4.0

[gyscos]

Updates cursive-core to 0.4.0, no change required.

[gyscos]

I added a commit adding blueprints for AlignedView, and a builder example showing how it can be used to reproduce the basic example using a builder config.

[fin-ger]

Hmm, the builder example is panicing on my machine with

thread 'main' panicked at examples/builder.rs:21:42:
called `Result::unwrap()` on an `Err` value: BlueprintNotFound("fixed_width")
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

[gyscos]

Oy :(

You're building with the builder feature? What OS are you running this on?
It relies on the inventory crate, which sometimes has compatibility issues with some platforms, for example dtolnay/inventory#52.

[fin-ger]

Ah, yes. With the builder feature it's working. I added it to the dev-dependencies.

[fin-ger]

Very nice! Thank you for the update ❤️ Will merge right away