Upgraded to Apache Log4j 2
via the Log4j 1.2 Bridge.
We are using the bridge due to the com.sendmail:jilter dependency requiring the 1.2 API.
Now supports Java 9+ modules. Due to still having filename-based automatic module dependencies,
*-SNAPSHOT versions include module-info.class while releases include the
Automatic-Module-Name manifest entry. To minimize the difference between these
modes, module-info.java does not perform any transitive requires.