This way there is now only one way to create a router:
```rust
use axum::{Router, handler::get};
let app = Router::new()
.route("/foo", get(handler))
.route("/foo", get(handler));
```
`nest` was changed in the same way:
```rust
use axum::Router;
let app = Router::new().nest("/foo", service);
```
These types were moved around in
https://github.com/tokio-rs/axum/pull/130 but re-export from their old
location for backwards compatibility.
This removes the re-exports.
https://github.com/tokio-rs/axum/pull/129 was a breaking change, in part
because I had to remove the `Copy` impl from `OnMethod`.
For the sake of future proofing I think we should remove other `Copy`
impls from services as well. We can always bring them back once things
have matured more.
These types no longer implement `Copy`:
- `EmptyRouter`
- `ExtractorMiddleware`
- `ExtractorMiddlewareLayer`
It cleans up the docs to have the futures in their own modules as users
are unlikely to look at them. Also matches the pattern used in tower
https://docs.rs/tower/0.4.8/tower/util/future/index.html.
Added re-exports to the old locations so its not a breaking change.
Previously extractors worked directly on `Request<B>` which meant you
had to do weird tricks like `mem::take(req.headers_mut())` to get owned
parts of the request.
This changes that instead to use a new `RequestParts` type that have
methods to "take" each part of the request. Without having to do weird
tricks.
Also removed the need to have `B: Default` for body extractors.
David Pedersen