Merge pull request #20 from Microsoft/jesbis-readmeupdate

fix contributing link in readme

README.md

@@ -16,7 +16,7 @@ You can download and use WinUI packages in your app using the NuGet package mana
 | [Microsoft.UI.Xaml](https://www.nuget.org/packages/Microsoft.UI.Xaml) | Controls and features for building apps for Windows 10 |
 | [Microsoft.UI.Xaml.Core.Direct](https://www.nuget.org/packages/Microsoft.UI.Xaml.Core.Direct) | Low-level APIs for creating middleware components. Not intended or required for general application use |
 
-You can also build a WinUI package yourself from source. See [Contributing to the Windows UI Library](CONTRIBUTING.MD) for more information on building and contributing to WinUI.
+You can also build a WinUI package yourself from source. See [Contributing to the Windows UI Library](CONTRIBUTING.md) for more information on building and contributing to WinUI.
 
 ### Build Status
 
@@ -99,4 +99,4 @@ For info on schedules and plans please see the high level plans see the [Windows
 
 This project collects usage data and sends it to Microsoft to help improve our products and services. Read Microsoft's [privacy statement to learn more](https://privacy.microsoft.com/privacystatement).
 
-For more information on telemetry implementation see the [developer guide](docs/developer_guide.md#Telemetry).
+For more information on telemetry implementation see the [developer guide](docs/developer_guide.md#Telemetry).