Implemented layer elements

Added a brush layer element
Corsair - Added ST100 RGB layout

src/Artemis.UI/Screens/GradientEditor/GradientEditorView.xaml

@@ -0,0 +1,16 @@
+<mah:MetroWindow x:Class="Artemis.UI.Screens.GradientEditor.GradientEditorView"
+                 xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+                 xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                 xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
+                 xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
+                 xmlns:gradientEditor="clr-namespace:Artemis.UI.Screens.GradientEditor"
+                 xmlns:materialDesign="http://materialdesigninxaml.net/winfx/xaml/themes"
+                 xmlns:mah="http://metro.mahapps.com/winfx/xaml/controls"
+                 mc:Ignorable="d"
+                 Title="Gradient Editor"
+                 Height="450" Width="800"
+                 d:DataContext="{d:DesignInstance {x:Type gradientEditor:GradientEditorViewModel}}">
+    <Grid>
+        <materialDesign:ColorPicker Color="{Binding CurrentColor}" />
+    </Grid>
+</mah:MetroWindow>