Implemented layer elements

Added a brush layer element
Corsair - Added ST100 RGB layout

src/Artemis.UI/Screens/Workshop/WorkshopView.xaml

@@ -4,6 +4,7 @@
              xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
              xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
              xmlns:local="clr-namespace:Artemis.UI.Screens.Workshop"
+             xmlns:materialDesign="http://materialdesigninxaml.net/winfx/xaml/themes"
              mc:Ignorable="d"
              d:DesignHeight="450" d:DesignWidth="800">
     <Grid>