This has the following nice benefits:
* The 'JsonValue' wrapper type is gone.
* 'Local{Request, Response}' natively support JSON/MessagePack.
* The 'json' and 'msgpack' limits are officially recognized.
* Soon, Rocket application will not require an explicit 'serde' dep.
This marks the beginning of the end of 'rocket_contrib'.
This commit entirely rewrites Rocket's URI parsing routines and
overhauls the 'uri!' macro resolving all known issues and removing any
potential limitations for compile-time URI creation. This commit:
* Introduces a new 'Reference' URI variant for URI-references.
* Modifies 'Redirect' to accept 'TryFrom<Reference>'.
* Introduces a new 'Asterisk' URI variant for parity.
* Allows creation of any URI type from a string literal via 'uri!'.
* Enables dynamic/static prefixing/suffixing of route URIs in 'uri!'.
* Unifies 'Segments' and 'QuerySegments' into one generic 'Segments'.
* Consolidates URI formatting types/traits into a 'uri::fmt' module.
* Makes APIs more symmetric across URI types.
It also includes the following less-relevant changes:
* Implements 'FromParam' for a single-segment 'PathBuf'.
* Adds 'FileName::is_safe()'.
* No longer reparses upstream request URIs.
Resolves#842.
Resolves#853.
Resolves#998.
...because loading up a Rocket while it's ignited is a bad idea.
More seriously, because 'Rocket.ignite()' will become an "execute
everything up to here" method.
The new examples directory...
* Contains a `README.md` explaining each example.
* Consolidates examples into more complete chunks.
* Is just better.
Resolves#1447.
Sergio Benitez