iconicsDrawableStart setVisible false not working
I have a `IconicsTextView` in XML:
   ```
<com.mikepenz.iconics.view.IconicsTextView
            android:id="@+id/txtInformation"
            style="@style/TextViewCaption"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:alpha="0.5"
            android:paddingTop="8dp"
            android:textColor="?attr/color_on_surface_background_themed"
            app:iiv_start_color="?attr/color_on_surface_background_themed"
            app:iiv_start_icon="@string/icon_barcode"
            app:iiv_start_size="20dp" />
```

when i set: `itemView.txtInformation.iconicsDrawableStart!!.setVisible(false, false)`
the Icon is still visible. It returns `true` (hasChanged) and false for `isVisible`.

I use:
- library version 4.0.2
- support library version 1.0.0
- Used gradle build tools version 3.5.3
- Used tooling / Android Studio version 3.5.3

I would be happy if anyone can check this or if i'm the only one with this bug.
