Added image preview when an image is used as attachment

additionally:
- added search icons
- solved problem of Scrollbars being shown too far from the right side
(all praise FX, Swing did not offer such a simple solution)
- relocated infoLabel into the highest row, is now located above the
messageList

src/main/resources/fxml/ChatScene.fxml

@@ -51,7 +51,7 @@
 				<Insets bottom="5.0" left="10.0" />
 			</GridPane.margin>
 			<padding>
-				<Insets bottom="5.0" left="5.0" right="5.0" top="5.0" />
+				<Insets bottom="5.0" left="5.0" right="2.0" top="5.0" />
 			</padding>
 			<contextMenu>
 				<ContextMenu anchorLocation="CONTENT_TOP_LEFT">
@@ -82,18 +82,17 @@
 				<Insets bottom="5.0" left="5.0" right="5.0" top="5.0" />
 			</padding>
 		</Button>
-		<ListView fx:id="messageList" prefHeight="257.0"
-			prefWidth="465.0" GridPane.columnIndex="1"
+		<ListView fx:id="messageList" GridPane.columnIndex="1"
 			GridPane.columnSpan="2147483647" GridPane.rowIndex="1"
 			GridPane.rowSpan="2">
 			<GridPane.margin>
 				<Insets left="5.0" right="10.0" />
 			</GridPane.margin>
 			<padding>
-				<Insets bottom="5.0" left="5.0" right="5.0" top="5.0" />
+				<Insets bottom="5.0" left="5.0" right="2.0" top="5.0" />
 			</padding>
 		</ListView>
-		<ButtonBar prefWidth="436.0" GridPane.columnIndex="1"
+		<ButtonBar buttonMinWidth="40.0" GridPane.columnIndex="1"
 			GridPane.columnSpan="2147483647" GridPane.halignment="CENTER"
 			GridPane.rowIndex="5" GridPane.valignment="BOTTOM">
 			<GridPane.margin>
@@ -101,7 +100,11 @@
 			</GridPane.margin>
 			<buttons>
 				<Button fx:id="attachmentButton" disable="true"
-					mnemonicParsing="false" onAction="#attachmentButtonClicked" />
+					mnemonicParsing="false" onAction="#attachmentButtonClicked">
+					<padding>
+						<Insets bottom="5.0" left="5.0" right="5.0" top="5.0" />
+					</padding>
+				</Button>
 				<Button fx:id="voiceButton" disable="true"
 					onAction="#voiceButtonClicked">
 					<padding>
@@ -177,7 +180,7 @@
 		</Label>
 		<Label fx:id="infoLabel" text="Something happened"
 			textFill="#faa007" visible="false" wrapText="true"
-			GridPane.columnIndex="1" GridPane.rowIndex="1">
+			GridPane.columnIndex="1">
 			<GridPane.margin>
 				<Insets bottom="5.0" left="5.0" right="5.0" top="5.0" />
 			</GridPane.margin>