Update README.md

Author: prochnowc

README.md

@@ -16,112 +16,15 @@ Latest development packages can be found on [MyGet](https://www.myget.org/galler
 The following packages are published as source NuGet packages, your application or library will not
 have a runtime dependency on them.
 
-| Package                          | Description                                                                   |
-|----------------------------------|-------------------------------------------------------------------------------|
-| `AppCoreNet.Attributes.Sources`  | Provides poly fills for .NET attributes.                                      |
-| `AppCoreNet.Diagnostics.Sources` | Provides static classes to ensure program contracts.                          |
-| `AppCoreNet.TypeHelpers.Sources` | Includes extensions for `Type` and `Assembly` and a fast activator for types. |
+| Package                                                                          | Description                                                                   |
+|----------------------------------------------------------------------------------|-------------------------------------------------------------------------------|
+| [`AppCoreNet.Attributes.Sources`](src/AppCoreNet.Attributes.Sources/README.md)   | Provides poly fills for .NET attributes.                                      |
+| [`AppCoreNet.Diagnostics.Sources`](src/AppCoreNet.Diagnostics.Sources/README.md) | Provides static classes to ensure program contracts.                          |
+| [`AppCoreNet.TypeHelpers.Sources`](src/AppCoreNet.TypeHelpers.Sources/README.md) | Includes extensions for `Type` and `Assembly` and a fast activator for types. |
 
 ## Contributing
 
 Contributions, whether you file an issue, fix some bug or implement a new feature, are highly appreciated. The whole user community
 will benefit from them.
 
 Please refer to the [Contribution guide](CONTRIBUTING.md).
-
-# Usage
-
-## AppCoreNet.Attributes.Sources
-
-This package includes sources for attributes which are defined in newer .NET versions (>= .NET Core 3.0) such as
-attributes required for nullable reference types, attributes required for the `required` keyword and others.
-
-If you are using the `Polyfill` or `Nullable` package these attributes are automatically disabled. You can control the
-inclusion of these attributes with the following MSBuild properties:
-
-- `AppCoreNetAttributesEnabled`
-  Enables/disables all attributes.
-- `AppCoreNetNullableAttributesEnabled`
-  Enables/disables the nullable attributes.
-- `AppCoreNetTrimmingAttributesEnabled`
-  Enables/disables the trimming attributes.
-
-
-For example:
-
-```msbuild
-<Project>
-  <PropertyGroup>
-    <AppCoreNetAttributesEnabled>false</AppCoreNetAttributesEnabled>
-  </PropertyGroup>
-</Project>
-```
-
-Will disable all attributes.
-
-## AppCoreNet.Diagnostics.Sources
-
-This package includes sources of static classes to ensure program contracts such as pre-conditions, post-conditions and
-invariants.
-
-### Pre-conditions
-
-Ensuring that some argument is not null:
-```csharp
-public void SomeMethod(object obj)
-{
-    // this will throw 'ArgumentNullException' if 'obj' is null
-    Ensure.Arg.NotNull(obj);
-}
-```
-
-Ensuring that some string argument is not null or empty/only whitespace:
-```csharp
-public void SomeMethod(string str)
-{
-    // this will throw 'ArgumentNullException' or 'ArgumentException' if 'str' is null or empty
-    Ensure.Arg.NotEmpty(str);
-}
-```
-
-Ensuring that some value argument is in range:
-```csharp
-public void SomeMethod(int val)
-{
-    // this will throw 'ArgumentOutOfRangeException' if 'val' is < 0 || > 10
-    Ensure.Arg.InRange(val, 0, 10);
-}
-```
-
-Other pre-condition checks are available: `Ensure.Arg.NotNullButEmpty()`, `Ensure.Arg.MinLength()`, `Ensure.Arg.MaxLength()`, `Ensure.Arg.OfType()`.
-
-Note that the package also supports annotations for ReSharper. Simply add the package `ReSharper.Annotations` to your
-project.
-
-## AppCoreNet.TypeHelpers.Sources
-
-Includes various extensions for the `Type` and `Assembly` classes to make your live easier when working
-with open generic types. Also provides a fast activator (factory) for dynamically instantiating types.
-
-Getting friendly type name for display, supports generics:
-```csharp
-class MyType<T> { }
-typeof(MyType<>).GetDisplayName() // returns 'MyNamespace.MyType<T>'
-```
-
-Creating an instance of a type:
-
-```csharp
-// creates an instance of 'MyType' with default constructor
-TypeActivator.CreateInstance<MyType>()
-
-// alternatively (if the Type is not known at compile time):
-TypeActivator.CreateInstance(typeof(MyType))
-```
-
-Checking if some type implements generic type:
-
-```csharp
-class StringList : List<string> { }
-typeof(StringList).IsClosedTypeOf(typeof(List<>))
-```