Preparations for the 1.0 release

* Less cluttered solution layout.
* Move examples to a repository of its own.
* Move Roslyn analyzer to a repository of its own.
* Enable central package management.
* Clean up csproj files.
* Add README file to NuGet packages.

src/Tests/Spectre.Console.Cli.Tests/Unit/CommandAppTests.Settings.cs

@@ -0,0 +1,21 @@
+namespace Spectre.Console.Tests.Unit.Cli;
+
+public sealed partial class CommandAppTests
+{
+    [Fact]
+    public void Should_Apply_Case_Sensitivity_For_Everything_By_Default()
+    {
+        // Given
+        var app = new CommandApp();
+
+        // When
+        var defaultSensitivity = CaseSensitivity.None;
+        app.Configure(config =>
+        {
+            defaultSensitivity = config.Settings.CaseSensitivity;
+        });
+
+        // Then
+        defaultSensitivity.ShouldBe(CaseSensitivity.All);
+    }
+}