Merge pull request NuGet#1501 from mairaw/metadata2

metadata fixes

Author: karann-msft

docs/concepts/package-installation-process.md

@@ -3,7 +3,7 @@ title: What happens when a package is installed?
 description: Detailed information about the package installation process
 author: karann-msft
 ms.author: karann
-ms.date: 0/20/2019
+ms.date: 06/20/2019
 ms.topic: conceptual
 ---
 

docs/release-notes/NuGet-5.1-RTM.md

@@ -1,3 +1,12 @@
+---
+title: NuGet 5.1 RTM Release Notes
+description: Release notes for NuGet 5.1 including new features, bug fixes, and DCRs.
+author: karann-msft
+ms.author: karann
+ms.date: 05/21/2019
+ms.topic: conceptual
+---
+
 # NuGet 5.1 Release Notes
 
 NuGet distribution vehicles: