Add support for publishing Java libraries with Maven This commit makes sure that Java projects and Java libraries can be published using the `maven` plugin. As the project is built with Gradle, we only need to add additional mappings for the `implementation`, `api` and `testImplementation` configurations, because the other configurations only make sense when building, not consuming.
Those are mapped to the following Maven scopes:
- `api` is mapped to `compile` - `implementation` is mapped to `runtime` - `testImplementation` is mapped to `test`
The `compileOnly` and `runtimeOnly` dependency buckets are only used from within a project, so should not appear in the generated pom file.