Changed compiler compliance to 11, modularized all packages (#29)

* added package- and module-info.java, changed JRE from 8 to 11

* moved ObjectProcessor into the processors package

Co-authored-by: CyB3RC0nN0R <kske@outlook.de>

src/main/java/envoy/server/processors/LoginCredentialProcessor.java

@@ -12,7 +12,6 @@ import envoy.data.Message.MessageStatus;
 import envoy.data.User;
 import envoy.data.User.UserStatus;
 import envoy.event.HandshakeRejectionEvent;
-import envoy.server.ObjectProcessor;
 import envoy.server.data.Message;
 import envoy.server.data.PersistenceManager;
 import envoy.server.net.ConnectionManager;