qml: allow to specify icon color in icon button for NavButton

Author: jarolrod

src/qml/controls/NavButton.qml

@@ -13,6 +13,7 @@ AbstractButton {
     property int textSize: 18
     property url iconSource: ""
     property Rectangle iconBackground: null
+    property color iconColor: Theme.color.neutral9
 
     padding: 0
     background: Rectangle {
@@ -55,7 +56,7 @@ AbstractButton {
                height: root.iconHeight
                width: root.iconWidth
                icon.source: root.iconSource
-               icon.color: Theme.color.neutral9
+               icon.color: root.iconColor
                icon.height: root.iconHeight
                icon.width: root.iconWidth
                background: root.iconBackground