Revert new experimental interfaces and classes

These will be postponed to the next minor version instead.

Author: emlun

NEWS

@@ -3,35 +3,6 @@
 * Added overloaded setter `RelyingPartyBuilder.origins(Optional<Set<String>>)`.
 * Added support for the CTAP2 `credProtect` extension.
 * Added support for the `prf` extension.
-* (Experimental) Added a new suite of interfaces, starting with
-  `CredentialRepositoryV2`. `RelyingParty` can now be configured with a
-  `CredentialRepositoryV2` instance instead of a `CredentialRepository`
-  instance. This changes the result of the `RelyingParty` builder to
-  `RelyingPartyV2`. `CredentialRepositoryV2` and `RelyingPartyV2` enable a suite
-  of new features:
- ** `CredentialRepositoryV2` does not assume that the application has usernames,
-    instead username support is modular. In addition to the
-    `CredentialRepositoryV2`, `RelyingPartyV2` can be optionally configured with
-    a `UsernameRepository` as well. If a `UsernameRepository` is not set, then
-    `RelyingPartyV2.startAssertion(StartAssertionOptions)` will fail at runtime
-    if `StartAssertionOptions.username` is set.
- ** `CredentialRepositoryV2` uses a new interface `CredentialRecord` to
-    represent registered credentials, instead of the concrete
-    `RegisteredCredential` class (although `RegisteredCredential` also
-    implements `CredentialRecord`). This provides implementations greater
-    flexibility while also automating the type conversion to
-    `PublicKeyCredentialDescriptor` needed in `startRegistration()` and
-    `startAssertion()`.
- ** `RelyingPartyV2.finishAssertion()` returns a new type `AssertionResultV2`
-    with a new method `getCredential()`, which returns the `CredentialRecord`
-    that was verified. The return type of `getCredential()` is generic and
-    preserves the concrete type of `CredentialRecord` returned by the
-    `CredentialRepositoryV2` implementation.
- ** NOTE: Experimental features may receive breaking changes without a major
-    version increase.
-* (Experimental) Added property `RegisteredCredential.transports`.
- ** NOTE: Experimental features may receive breaking changes without a major
-    version increase.
 * (Experimental) Added option `FinishRegistrationOptions.isConditionalCreate` to
   allow UP=0 in registration response for registration ceremonies with
   `mediation: "conditional"`.