UI: Button to set emulator time based on system time in settings, under the time settings.

Partially resolves #355. I think that wanted automatic. If automatic functionality is still desired even with this change then that will be considered.

src/Ryujinx/UI/Views/Settings/SettingsSystemView.axaml

@@ -182,7 +182,20 @@
                             Width="350"
                             ToolTip.Tip="{ext:Locale TimeTooltip}" />
                     </StackPanel>
-                    <StackPanel Margin="0,0,0,10"
+                    <StackPanel
+                        Margin="250,0,0,10"
+                        Orientation="Horizontal">
+                        <Button
+                            VerticalAlignment="Center"
+                            Click="MatchSystemTime_OnClick"
+                            Background="{DynamicResource SystemAccentColor}"
+                            Width="350"
+                            ToolTip.Tip="{ext:Locale TimeTooltip}">
+                            <TextBlock Text="Match System Time" />
+                        </Button>
+                    </StackPanel>
+                    <Separator />
+                    <StackPanel Margin="0,10,0,10"
                                 Orientation="Horizontal">
                         <TextBlock
                             VerticalAlignment="Center"

src/Ryujinx/UI/Views/Settings/SettingsSystemView.axaml.cs

@@ -1,5 +1,7 @@
 using Avalonia.Controls;
+using Avalonia.Interactivity;
 using Ryujinx.Ava.UI.ViewModels;
+using System;
 using TimeZone = Ryujinx.Ava.UI.Models.TimeZone;
 
 namespace Ryujinx.Ava.UI.Views.Settings
@@ -33,5 +35,7 @@ namespace Ryujinx.Ava.UI.Views.Settings
                 ViewModel.ValidateAndSetTimeZone(timeZone.Location);
             }
         }
+
+        private void MatchSystemTime_OnClick(object sender, RoutedEventArgs e) => ViewModel.MatchSystemTime();
     }
 }