Fix some issues with CSV field mapping dialog in Dark Mode on 10.14

Note: some issues remain because 10.14 uses „secondaryLabelColor“ as border color for boxes, which does not exist before 10.10

Also on 10.9 if no color is set as borderColor/fillColor for boxes, it will default to black, while in 10.14 it defaults to „OS default“.

Author: dmoagx

Interfaces/English.lproj/DataMigrationDialog.xib

@@ -80,7 +80,7 @@
                             <autoresizingMask key="autoresizingMask" widthSizable="YES" heightSizable="YES"/>
                         </view>
                         <color key="borderColor" white="0.0" alpha="0.41999999999999998" colorSpace="calibratedWhite"/>
-                        <color key="fillColor" white="0.93000000719999998" alpha="1" colorSpace="calibratedWhite"/>
+                        <color key="fillColor" white="0.0" alpha="0.0" colorSpace="calibratedWhite"/>
                     </box>
                     <box autoresizesSubviews="NO" title="Box" boxType="custom" borderType="line" titlePosition="noTitle" id="14" userLabel="Header Box (Box)">
                         <rect key="frame" x="-1" y="308" width="636" height="41"/>
@@ -140,7 +140,7 @@
                             </subviews>
                         </view>
                         <color key="borderColor" white="0.0" alpha="0.41999999999999998" colorSpace="calibratedWhite"/>
-                        <color key="fillColor" red="0.9450981021" green="0.9450981021" blue="0.9450981021" alpha="1" colorSpace="deviceRGB"/>
+                        <color key="fillColor" white="0.0" alpha="0.0" colorSpace="calibratedWhite"/>
                     </box>
                     <scrollView autohidesScrollers="YES" horizontalLineScroll="18" horizontalPageScroll="10" verticalLineScroll="18" verticalPageScroll="10" hasHorizontalScroller="NO" usesPredominantAxisScrolling="NO" id="13">
                         <rect key="frame" x="-1" y="129" width="636" height="144"/>
@@ -363,7 +363,6 @@ DQ
                         <autoresizingMask key="autoresizingMask" widthSizable="YES" flexibleMaxX="YES" flexibleMinY="YES"/>
                         <pathCell key="cell" controlSize="small" lineBreakMode="truncatingMiddle" selectable="YES" focusRingType="none" alignment="left" id="26">
                             <font key="font" metaFont="smallSystem"/>
-                            <color key="backgroundColor" red="0.92941182850000004" green="0.92941182850000004" blue="0.92941182850000004" alpha="1" colorSpace="deviceRGB"/>
                         </pathCell>
                     </pathControl>
                     <button id="111">