Sessions
--------
This commit removes the `Session` type in favor of methods on the
`Cookies` types that allow for adding, removing, and getting private
(signed and encrypted) cookies. These methods provide a superset of
the functionality of `Session` while also being a minimal addition to
the existing API. They can be used to implement the previous `Session`
type as well as other forms of session storage. The new methods are:
* Cookie::add_private(&mut self, Cookie)
* Cookie::remove_private(&mut self, Cookie)
* Cookie::get_private(&self, &str)
Resolves#20
Testing
-------
This commit removes the `rocket::testing` module. It adds the
`rocket::local` module which provides a `Client` type for local
dispatching of requests against a `Rocket` instance. This `local`
package subsumes the previous `testing` package.
Rocket Examples
---------------
The `forms`, `optional_result`, and `hello_alt_methods` examples have
been removed. The following example have been renamed:
* extended_validation -> form_validation
* hello_ranks -> ranking
* from_request -> request_guard
* hello_tls -> tls
Other Changes
-------------
This commit also includes the following smaller changes:
* Config::{development, staging, production} constructors have been
added for easier creation of default `Config` structures.
* The `Config` type is exported from the root.
* `Request` implements `Clone` and `Debug`.
* `Request::new` is no longer exported.
* A `Response::body_bytes` method was added to easily retrieve a
response's body as a `Vec<u8>`.
