Support JWKs with no algorithm

This patch was authored and released by @tanner0101.

Adds support for JSON Web Keys that do not specify an algorithm (#34).

JWKs are now stored directly in JWTSigners via the use(jwk:) method. When a request to verify a JWT is received that matches a JWK, both the JWT and the JWK's algorithm header is checked. A signer is then created on the fly to handle the request.

Add support for Apple Silicon

This patch was authored by @0xTim and released by @tanner0101.

Adds support for Apple Silicon (#32).

Boring SSL update

This patch was authored by @0xTim and released by @tanner0101.

Brings in the latest version of BoringSSL (#31).

Add typ, cty fields in the JWT header

This patch was authored by @Maxim-Inv and released by @tanner0101.

Adds typ and cty fields to the JWT header (#25, fixes #5).

• Add typ header as parameter making "JWT" the default.

• Allow setting cty during JWT signing.

let signer = JWTSigner.hs256(key: keyData)`
let token = try signer.sign(payload, cty: "twilio-fpa;v=1")

Migrate HMAC to Crypto

This patch was authored and released by @0xTim.

Migrate all the HMAC code away from BoringSSL to Swift Crypto (#24).

Create a generic `JWTMultiValueClaim` protocol

This patch was authored and released by @gwynne.

• Allows much simpler implementation of JWT claims with multiple values.
• Switches to this implementation for AudienceClaim

Give `AudienceClaim` more powers

This patch was authored and released by @gwynne.

• Allow AudienceClaim to represent more than one audience, per RFC 7519 § 4.1.3
• Add verifyIntendedAudience(includes:) method for conveniently verifying that the audience is the intended one.
• Add unit tests for new functionality.

Because the Value type of AudienceClaim is now [String] instead of String, this change is API-breaking!

This would normally require a semver-major update, but as the package is still in RC, I think it can scrape past with a semver-minor, especially since the change is to obey spec.

Added the nonce_supported claim to AppleIdentityToken

The claim was missing.

This patch was authored and released by @grosch.

Release Candidate 1

Updates to Swift 5.2.

Release candidates represent the final shift toward focusing on bug fixes and documentation. Breaking changes will only be accepted for critical issues. We expect a final release of this package shortly after Swift 5.2's release date.

Fixes Codable support for LocaleClaim

Previously, LocaleClaims were not decoded from JWTs correctly. This patch fixes their behavior and adds tests to prevent regression.