Add `reachability-metadata.json` to all Log4j modules (#3053)
* Add `reachability-metadata.json` to all Log4j modules
This PR adds a plugin processor that generates a GraalVM reachability metadata file and bundles it with each Log4j module.
After this change, GraalVM will be able to handle Log4j Core without any user intervention.
**Note**: I also added a static `resource-config.json` file that specifies that all resources starting with `log4j2` and the plugin descriptor must be included in the GraalVM image.
This also includes a small change to Log4j API to include in the GraalVM image the following 3 resource:
* `log4j2.component.properties`,
* `log4j2.simplelog.properties`,
* `log4j2.StatusLogger.properties`
12 files changed
