dotnet-state-machine#553 Add NuGet package README; update compatibili…

…ty statement in README.md.

README.md

@@ -241,7 +241,7 @@ Setting this is vital within a Microsoft Orleans Grain for example, which requir
 
 ## Building
 
-Stateless runs on .NET 4.0+ and practically all modern .NET platforms by targeting .NET Standard 1.0 and .NET Standard2.0. Visual Studio 2017 or later is required to build the solution.
+Stateless runs on .NET runtime version 4+ and practically all modern .NET platforms by targeting .NET Framework 4.6.2, .NET Standard 2.0 and .NET 8.0. Visual Studio 2017 or later is required to build the solution.
 
 
 ## Contributing
@@ -256,5 +256,3 @@ This page is an almost-complete description of Stateless, and its explicit aim i
 Please use the issue tracker or the if you'd like to report problems or discuss features.
 
 (_Why the name? Stateless implements the set of rules regarding state transitions, but, at least when the delegate version of the constructor is used, doesn't maintain any internal state itself._)
-
-[Visual Studio 2015 and .NET Core]: https://www.microsoft.com/net/core

src/Stateless/Stateless.csproj

@@ -21,6 +21,7 @@
     <GenerateAssemblyVersionAttribute>false</GenerateAssemblyVersionAttribute>
     <PackageLicenseExpression>Apache-2.0</PackageLicenseExpression>
     <RepositoryType>git</RepositoryType>
+    <PackageReadmeFile>README.md</PackageReadmeFile>
   </PropertyGroup>
 
   <PropertyGroup Label="SourceLink">
@@ -45,4 +46,8 @@
   <ItemGroup Label="SourceLink">
     <PackageReference Include="Microsoft.SourceLink.GitHub" Version="1.1.1" PrivateAssets="All"/>
   </ItemGroup>
+
+  <ItemGroup>
+    <None Include="docs\README.md" Pack="true" PackagePath="\"/>
+  </ItemGroup>
 </Project>

src/Stateless/docs/README.md

@@ -0,0 +1,56 @@
+# Stateless
+
+**Create *state machines* and lightweight *state machine-based workflows* directly in .NET code:**
+
+```csharp
+var phoneCall = new StateMachine<State, Trigger>(State.OffHook);
+
+phoneCall.Configure(State.OffHook)
+    .Permit(Trigger.CallDialled, State.Ringing);
+
+phoneCall.Configure(State.Connected)
+    .OnEntry(t => StartCallTimer())
+    .OnExit(t => StopCallTimer())
+    .InternalTransition(Trigger.MuteMicrophone, t => OnMute())
+    .InternalTransition(Trigger.UnmuteMicrophone, t => OnUnmute())
+    .InternalTransition<int>(_setVolumeTrigger, (volume, t) => OnSetVolume(volume))
+    .Permit(Trigger.LeftMessage, State.OffHook)
+    .Permit(Trigger.PlacedOnHold, State.OnHold);
+
+// ...
+
+phoneCall.Fire(Trigger.CallDialled);
+Assert.AreEqual(State.Ringing, phoneCall.State);
+```
+
+This project, as well as the example above, was inspired by 
+[Simple State Machine (Archived)](https://web.archive.org/web/20170814020207/http://simplestatemachine.codeplex.com/).
+
+## Features
+
+Most standard state machine constructs are supported:
+
+ * Generic support for states and triggers of any .NET type (numbers, strings, enums, etc.)
+ * Hierarchical states
+ * Entry/exit actions for states
+ * Guard clauses to support conditional transitions
+ * Introspection
+
+Some useful extensions are also provided:
+
+ * Ability to store state externally (for example, in a property tracked by an ORM)
+ * Parameterised triggers
+ * Reentrant states
+ * Export to DOT graph
+
+## Documentation
+
+For guidance on how to use Stateles, the 
+[project README file](https://github.com/dotnet-state-machine/stateless?tab=readme-ov-file#stateless----) 
+contains documentation and code examples. The source repository also includes a few 
+[example projects](https://github.com/dotnet-state-machine/stateless/tree/dev/example).
+
+## Contributing
+
+We welcome contributions to this project. Check 
+[CONTRIBUTING.md](https://github.com/dotnet-state-machine/stateless/blob/dev/CONTRIBUTING.md) for more info.