Support module path scanning for "classpath*:" resource prefix

[sbrannen]

In light of the findings from investigating #21515, we should introduce implicit support for scanning the module path whenever the classpath*: resource prefix is used.

This should allow existing applications relying on classpath*: semantics to work when migrating to the Java module system (for use cases not already supported by ClassLoader-based class path scanning).

For example, @ComponentScan should effectively work the same when an application is deployed on the class path or module path.

[sbrannen]

This issue has been resolved for inclusion in 6.0 M5.

In the interim, feel free to try out 6.0 snapshots for applications deployed with patched modules.

I've created a new repository for demonstrating the use of the Spring Framework with the Java Module System: https://github.com/sbrannen/spring-module-system

That repository currently contains a single maven-surefire-patched-module project which demonstrates support for @ComponentScan in a patched module using Maven Surefire.