add hub specific tab to vault options

src/main/resources/fxml/vault_options.fxml

@@ -36,5 +36,13 @@
 				<fx:include source="vault_options_masterkey.fxml"/>
 			</content>
 		</Tab>
+		<Tab fx:id="hubTab" id="HUB" text="Recovery"> <!-- is removed in controller, when config.keyid.scheme is not cryptomator-hub -->
+			<graphic>
+				<FontAwesome5IconView glyph="KEY"/>
+			</graphic>
+			<content>
+				<fx:include source="vault_options_hub.fxml"/>
+			</content>
+		</Tab>
 	</tabs>
 </TabPane>

src/main/resources/fxml/vault_options_hub.fxml

@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="UTF-8"?>
+
+<?import org.cryptomator.ui.controls.FontAwesome5IconView?>
+<?import javafx.geometry.Insets?>
+<?import javafx.scene.control.Button?>
+<?import javafx.scene.control.Label?>
+<?import javafx.scene.layout.Region?>
+<?import javafx.scene.layout.VBox?>
+<VBox xmlns:fx="http://javafx.com/fxml"
+	  xmlns="http://javafx.com/javafx"
+	  fx:controller="org.cryptomator.ui.vaultoptions.HubOptionsController"
+	  spacing="6"
+	  alignment="TOP_CENTER">
+	<padding>
+		<Insets topRightBottomLeft="12"/>
+	</padding>
+</VBox>