Add example for using document previewer.

QuestPDF.Previewer.Examples/Program.cs

@@ -0,0 +1,41 @@
+using QuestPDF.Fluent;
+using QuestPDF.Helpers;
+using QuestPDF.Infrastructure;
+using QuestPDF.Previewer;
+
+Document
+    .Create(container =>
+    {
+        container.Page(page =>
+        {
+            page.Size(PageSizes.A4);
+            page.Margin(2, Unit.Centimetre);
+            page.PageColor(Colors.White);
+            page.DefaultTextStyle(x => x.FontSize(20));
+
+            page.Header()
+                .Text("Hot Reload!")
+                .SemiBold().FontSize(36).FontColor(Colors.Blue.Darken2);
+
+            page.Content()
+                .PaddingVertical(1, Unit.Centimetre)
+                .Column(x =>
+                {
+                    x.Spacing(20);
+
+                    x.Item().Text("VS: Start in debug mode with 'Hot Reload on Save' enabled.");
+                    x.Item().Text("VSCode: Use dotnet watch to instantly see your changes in the previewer.");
+
+                    x.Item().Text("Try it out here.");
+                });
+
+            page.Footer()
+                .AlignCenter()
+                .Text(x =>
+                {
+                    x.Span("Page ");
+                    x.CurrentPageNumber();
+                });
+        });
+    })
+    .ShowInPreviewer();