Added a new concept of deep link handlers.

[rossbacher]

From the addition to the README.md:

You can annotate a Kotlin object that is extending com.airbnb.deeplinkdispatch.handler.DeepLinkHandler with an @DeepLink annotation. e.g.DeepLinkHandler.

@DeepLink("foo://example.com/handlerDeepLink/{param1}?query1={queryParameter}")
object ProjectDeepLinkHandler : DeepLinkHandler<ProjectDeepLinkHandlerArgs>() {
    override fun handleDeepLink(parameters: ProjectDeepLinkHandlerArgs) {
        /**
         * From here any internal/3rd party navigation framework can be called the provided args.
         */
    }
}
data class ProjectDeepLinkHandlerArgs(
    @DeeplinkParam("param1", DeepLinkParamType.Path) val number: Int,
    @DeeplinkParam("query1", DeepLinkParamType.Query) val flag: Boolean?,
)

DeepLinkDispatch will then call handleDeepLink function in your handler with the path placeholders and queryParameters converted into an instance of the specified type class.

This will give compile time safety as all placeholders and query parameters specified in the template inside the @DeepLink annotation must be present in the arguments class for the processor to pass. This is also true the other way around as all fields in the arguments class must be annotated and must be present in the template inside the annotation.

From this function side the handler you can now call into any internal or 3rd party navigation system without any Intent being fired at all and with type safety for your arguments.DeepLink

Note: That even though they must be listed in the template and annotation argument values annotated with DeepLinkParamType.Query can be null as they are allowed to not be present in the matched url. Type values that cannot be converted (e.g. a value that cannot be converted to a number) 0 is assumed for non nullable DeepLinkParamType.Path values and null is returned for DeepLinkParamType.Query values.

Changes

• Converted BaseDeepLinkDelegate to Kotlin which has some impact on Nullability.
• Converted DeepLinkEntry to a sealed class with 3 subtypes: ActivityDeeplinkEntry, MethodDeeplinkEntry and `HandlerDeeplinkEntry1
• Updated index to store the deep link entry type inside the index.