docs: Update readme after packages split

Readme.md

@@ -1,7 +1,18 @@
 # Uno.Core
 
-Uno.Core is nventive's attempt at filling some gaps in the existing .net framework and related technologies; hence reducing friction
-and increasing the predictability of the api. It consists of a set of helpers, extension methods and additional abstractions.
+Uno.Core is nventive's attempt at filling some gaps in the existing .NET Base Class Library and related technologies. It reduces friction
+and increases the predictability of the API. It consists of a set of helpers, extension methods and additional abstractions.
+
+The following packages are available:
+- `Uno.Core.Extensions` is a set of extension methods on common .NET times such as `Func<>`, `Action<>`, `Regex`, `Stream`, etc...
+- `Uno.Core.Extensions.Collections` is a set of collection-related extensions and types such as `ICollection`, `IEnumerable`, `Memory`, etc...
+- `Uno.Core.Extensions.Disposables` is a set of `IDisposable` implementations
+- `Uno.Core.Extensions.Equality` is a set of specialized equality comparers
+- `Uno.Core.Extensions.Logging` is a set of extension methods for `Microsoft.Logging.Extensions` provided types
+- `Uno.Core.Extensions.Logging.Singleton` is a helper to get a singleton-based `this.Log()` logging.
+- `Uno.Core.Extensions.Threading` is a set of helpers for threading such as `Uno.Transactional` or `Uno.Threading.FastAsyncLock`.
+- `Uno.Core.Extensions.Compatibility` is present for compatibility with existing applications
+- `Uno.Core` is a meta-package which references all above packages.
 
 ## Build status
 
@@ -9,9 +20,6 @@ and increasing the predictability of the api. It consists of a set of helpers, e
 | ------ | ------ | ------ | ------ |
 | development | master |[![Build Status](https://dev.azure.com/uno-platform/Uno%20Platform/_apis/build/status/Uno%20Platform/Uno.Core-CI?branchName=master)](https://dev.azure.com/uno-platform/Uno%20Platform/_build/latest?definitionId=39?branchName=master) | [![NuGet](https://img.shields.io/nuget/v/Uno.Core.svg)](https://www.nuget.org/packages/Uno.Core/) |
 
-## Documentation
-_Coming soon._
-
 # Have questions? Feature requests? Issues?
 
 Make sure to visit our [StackOverflow](https://stackoverflow.com/questions/tagged/uno-platform), [create an issue](https://github.com/nventive/Uno.SourceGeneration/issues) or [visit our gitter](https://gitter.im/uno-platform/Lobby).