UI - Added gradient editor dialog

src/Artemis.UI.Shared/ColorPicker.xaml

@@ -68,14 +68,8 @@
                                 <RepeatButton Command="{x:Static Slider.IncreaseLarge}" Style="{StaticResource MaterialDesignHorizontalColorSliderTrackRepeatButton}" />
                             </Track.IncreaseRepeatButton>
                             <Track.Thumb>
-                                <Thumb
-                                    x:Name="Thumb"
-                                    Width="20"
-                                    Height="20"
-                                    VerticalAlignment="Center"
-                                    Focusable="False"
-                                    OverridesDefaultStyle="True"
-                                    Template="{StaticResource MaterialDesignColorSliderThumb}">
+                                <Thumb x:Name="Thumb" Width="20" Height="20" VerticalAlignment="Center" Focusable="False" OverridesDefaultStyle="True"
+                                       Template="{StaticResource MaterialDesignColorSliderThumb}">
                                     <Thumb.Foreground>
                                         <SolidColorBrush
                                             Color="{Binding Color, RelativeSource={RelativeSource AncestorType={x:Type UserControl}}, Mode=OneWay, Converter={StaticResource ColorToSolidColorConverter}}" />
@@ -97,7 +91,6 @@
                  MinWidth="95"
                  MaxLength="9"
                  Margin="0"
-                 Padding="-1"
                  HorizontalAlignment="Stretch" />
 
         <Border Width="15"