Added better dependency injection mechanism and purified LoginScene

one thing could for whatever reason not be avoided: Even though the
processors of the caches inside WriteProxy are initialized, they somehow
get "de-initialized" and have to be initialized again...

client/src/main/java/envoy/client/data/Cache.java

@@ -51,6 +51,12 @@ public final class Cache<T> implements Consumer<T>, Serializable {
 	 */
 	public void setProcessor(Consumer<T> processor) { this.processor = processor; }
 
+	/**
+	 * @return the processor
+	 * @since Envoy Client v0.2-beta
+	 */
+	public Consumer<T> getProcessor() { return processor; }
+
 	/**
 	 * Relays all cached elements to the processor.
 	 *

client/src/main/java/envoy/client/data/Context.java

@@ -0,0 +1,97 @@
+package envoy.client.data;
+
+import javafx.stage.Stage;
+
+import envoy.client.net.Client;
+import envoy.client.net.WriteProxy;
+import envoy.client.ui.SceneContext;
+
+/**
+ * Provides access to commonly used objects.
+ * <p>
+ * Project: <strong>client</strong><br>
+ * File: <strong>Context.java</strong><br>
+ * Created: <strong>01.09.2020</strong><br>
+ *
+ * @author Leon Hofmeister
+ * @since Envoy Client v0.2-beta
+ */
+public class Context {
+
+	private final Client client = new Client();
+
+	private WriteProxy writeProxy;
+
+	private LocalDB localDB;
+
+	private Stage stage;
+
+	private SceneContext sceneContext;
+
+	private static final Context instance = new Context();
+
+	/**
+	 * @return the instance of {@code Context} used throughout Envoy
+	 * @since Envoy Client v0.2-beta
+	 */
+	public static Context getInstance() { return instance; }
+
+	/**
+	 * @return the localDB
+	 * @since Envoy Client v0.2-beta
+	 */
+	public LocalDB getLocalDB() { return localDB; }
+
+	/**
+	 * @param localDB the localDB to set
+	 * @since Envoy Client v0.2-beta
+	 */
+	public void setLocalDB(LocalDB localDB) { this.localDB = localDB; }
+
+	/**
+	 * @return the sceneContext
+	 * @since Envoy Client v0.2-beta
+	 */
+	public SceneContext getSceneContext() { return sceneContext; }
+
+	/**
+	 * @param sceneContext the sceneContext to set. Additionally sets the stage.
+	 * @since Envoy Client v0.2-beta
+	 */
+	public void setSceneContext(SceneContext sceneContext) {
+		this.sceneContext	= sceneContext;
+		stage				= sceneContext.getStage();
+	}
+
+	/**
+	 * @return the client
+	 * @since Envoy Client v0.2-beta
+	 */
+	public Client getClient() { return client; }
+
+	/**
+	 * @return the writeProxy
+	 * @since Envoy Client v0.2-beta
+	 */
+	public WriteProxy getWriteProxy() { return writeProxy; }
+
+	/**
+	 * @return the stage
+	 * @since Envoy Client v0.2-beta
+	 */
+	public Stage getStage() { return stage; }
+
+	private Context() {}
+
+	/**
+	 * @param writeProxy the writeProxy to set
+	 * @since Envoy Client v0.2-beta
+	 */
+	public void setWriteProxy(WriteProxy writeProxy) { this.writeProxy = writeProxy; }
+
+	/**
+	 * @param stage the stage to set
+	 * @since Envoy Client v0.2-beta
+	 */
+	public void setStage(Stage stage) { this.stage = stage; }
+}