Core - Added ColorGradient type to use for.. gradients!

Core - Initialisation process no longer takes place in core constructor and is no longer async
UI - Fixed exceptions during init not being shown
Gradient editor - Started work on this

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

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+<controls:MaterialWindow x:Class="Artemis.UI.Shared.Screens.GradientEditor.GradientEditor"
+                         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:local="clr-namespace:Artemis.UI.Shared.Screens.GradientEditor"
+                         xmlns:controls="clr-namespace:MaterialDesignExtensions.Controls;assembly=MaterialDesignExtensions"
+                         xmlns:s="https://github.com/canton7/Stylet"
+                         xmlns:materialDesign="http://materialdesigninxaml.net/winfx/xaml/themes"
+                         mc:Ignorable="d"
+                         Title="Gradient Editor"
+                         Background="{DynamicResource MaterialDesignPaper}"
+                         FontFamily="pack://application:,,,/MaterialDesignThemes.Wpf;component/Resources/Roboto/#Roboto"
+                         UseLayoutRounding="True"
+                         Width="800"
+                         Height="450"
+                         ResizeMode="NoResize"
+                         Icon="/Resources/Images/Logo/logo-512.png"
+                         d:DesignHeight="450"
+                         d:DesignWidth="800">
+    <Grid>
+
+    </Grid>
+</controls:MaterialWindow>

src/Artemis.UI.Shared/Screens/GradientEditor/GradientEditor.xaml.cs

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+using System.Windows;
+using Artemis.Core.Models.Profile;
+using MaterialDesignExtensions.Controls;
+
+namespace Artemis.UI.Shared.Screens.GradientEditor
+{
+    /// <summary>
+    ///     Interaction logic for GradientEditor.xaml
+    /// </summary>
+    public partial class GradientEditor : MaterialWindow
+    {
+        public GradientEditor(DependencyProperty colorGradientProperty)
+        {
+            ColorGradientProperty = colorGradientProperty;
+            InitializeComponent();
+        }
+
+        public DependencyProperty ColorGradientProperty { get; }
+
+        public ColorGradient ColorGradient
+        {
+            get => (ColorGradient) GetValue(ColorGradientProperty);
+            set => SetValue(ColorGradientProperty, value);
+        }
+    }
+}