Make YesNtInterpreter usable as a library and add AddStatement method to be able to define custom statement

YesNt.Interpreter.App/Program.cs

@@ -0,0 +1,14 @@
+using System;
+
+using YesNt.Interpreter.Runtime;
+
+if (args.Length == 1)
+{
+    YesNtInterpreter interpreter = new YesNtInterpreter();
+    interpreter.Initialize();
+    interpreter.Execute(args[0]);
+}
+else
+{
+    Console.WriteLine("No path specified!");
+}

YesNt.Interpreter.App/YesNt.Interpreter.App.csproj

@@ -0,0 +1,13 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>net8.0</TargetFramework>
+    <OutputType>Exe</OutputType>
+    <Platforms>AnyCPU;x64</Platforms>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\YesNt.Interpreter\YesNt.Interpreter.csproj" />
+  </ItemGroup>
+
+</Project>