Update copyright headers

***NO_CI***

Author: josesimoes

nanoFramework.CoreLibrary.DELIVERABLES.nuspec

@@ -11,7 +11,7 @@
     <developmentDependency>false</developmentDependency>
     <projectUrl>https://github.com/nanoframework/lib-CoreLibrary</projectUrl>
     <iconUrl>https://secure.gravatar.com/avatar/97d0e092247f0716db6d4b47b7d1d1ad</iconUrl>
-    <copyright>Copyright (c) 2018 The nanoFramework project contributors</copyright>    
+    <copyright>Copyright (c) .NET Foundation and Contributors</copyright>    
     <description>** DON'T REFERENCE THIS PACKAGE ** Not meant for development. This package includes the deliverable artifacts of the base class library (mscorlib) of nanoFramework. These are for testing purposes and for updating the native code base of the core library.</description>
     <summary>nanoFramework.CoreLibrary.DELIVERABLES is not meant for development</summary>
     <tags></tags>

nanoFramework.CoreLibrary.NoReflection.nuspec

@@ -13,7 +13,7 @@
     <projectUrl>https://github.com/nanoframework/lib-CoreLibrary</projectUrl>
     <iconUrl>https://secure.gravatar.com/avatar/97d0e092247f0716db6d4b47b7d1d1ad</iconUrl>
     <repository type="git" url="https://github.com/nanoframework/lib-CoreLibrary" commit="$commit$" />
-    <copyright>Copyright (c) 2019 The nanoFramework project contributors</copyright>    
+    <copyright>Copyright (c) .NET Foundation and Contributors</copyright>    
     <description>This package includes the nanoFramework.CoreLibrary assembly for nanoFramework C# projects **WITHOUT** the System.Reflection API.&#10;This package requires a target with mscorlib v$nativeVersion$.&#10;There is another version that includes the System.Reflection API.</description>
     <summary>This package includes the nanoFramework.CoreLibrary assembly for nanoFramework C# projects **WITHOUT** the System.Reflection API.</summary>
     <tags>nanoFramework C# csharp netmf netnf nanoFramework.CoreLibrary</tags>

nanoFramework.CoreLibrary.nuspec

@@ -13,7 +13,7 @@
     <projectUrl>https://github.com/nanoframework/lib-CoreLibrary</projectUrl>
     <iconUrl>https://secure.gravatar.com/avatar/97d0e092247f0716db6d4b47b7d1d1ad</iconUrl>
     <repository type="git" url="https://github.com/nanoframework/lib-CoreLibrary" commit="$commit$" />
-    <copyright>Copyright (c) 2018 The nanoFramework project contributors</copyright>    
+    <copyright>Copyright (c) .NET Foundation and Contributors</copyright>    
     <description>This package includes the nanoFramework.CoreLibrary assembly for nanoFramework C# projects.&#10;This package requires a target with mscorlib v$nativeVersion$.&#10;In case you don't need the System.Reflection API there is another NuGet package without this API.</description>
     <summary>This package includes the nanoFramework.CoreLibrary assembly for nanoFramework C# projects.</summary>
     <tags>nanoFramework C# csharp netmf netnf nanoFramework.CoreLibrary</tags>

nanoFramework.CoreLibrary/Friends.cs

@@ -1,5 +1,5 @@
 //
-// Copyright (c) 2017 The nanoFramework project contributors
+// Copyright (c) .NET Foundation and Contributors
 // See LICENSE file in the project root for full license information.
 //
 

nanoFramework.CoreLibrary/System/AppDomain.cs

@@ -1,5 +1,5 @@
 //
-// Copyright (c) 2017 The nanoFramework project contributors
+// Copyright (c) .NET Foundation and Contributors
 // Portions Copyright (c) Microsoft Corporation.  All rights reserved.
 // See LICENSE file in the project root for full license information.
 //

nanoFramework.CoreLibrary/System/AppDomainUnloadedException.cs

@@ -1,5 +1,5 @@
 //
-// Copyright (c) 2017 The nanoFramework project contributors
+// Copyright (c) .NET Foundation and Contributors
 // Portions Copyright (c) Microsoft Corporation.  All rights reserved.
 // See LICENSE file in the project root for full license information.
 //

nanoFramework.CoreLibrary/System/ApplicationException.cs

@@ -1,5 +1,5 @@
 //
-// Copyright (c) 2017 The nanoFramework project contributors
+// Copyright (c) .NET Foundation and Contributors
 // Portions Copyright (c) Microsoft Corporation.  All rights reserved.
 // See LICENSE file in the project root for full license information.
 //

nanoFramework.CoreLibrary/System/ArgumentException.cs

@@ -1,5 +1,5 @@
 //
-// Copyright (c) 2017 The nanoFramework project contributors
+// Copyright (c) .NET Foundation and Contributors
 // Portions Copyright (c) Microsoft Corporation.  All rights reserved.
 // See LICENSE file in the project root for full license information.
 //

nanoFramework.CoreLibrary/System/ArgumentNullException.cs

@@ -1,5 +1,5 @@
 //
-// Copyright (c) 2017 The nanoFramework project contributors
+// Copyright (c) .NET Foundation and Contributors
 // Portions Copyright (c) Microsoft Corporation.  All rights reserved.
 // See LICENSE file in the project root for full license information.
 //

nanoFramework.CoreLibrary/System/ArgumentOutOfRangeException.cs

@@ -1,5 +1,5 @@
 //
-// Copyright (c) 2017 The nanoFramework project contributors
+// Copyright (c) .NET Foundation and Contributors
 // Portions Copyright (c) Microsoft Corporation.  All rights reserved.
 // See LICENSE file in the project root for full license information.
 //