Rename ReleaseNotes.txt to ReleaseNotes.md

Also trigger new build for nuget to update package references

Author: scott-xu

ReleaseNotes.txt ReleaseNotes.mdReleaseNotes.txt renamed to ReleaseNotes.md

@@ -6,4 +6,4 @@ Version 3.0.0.0
 ---------------
 Removed: No web builds. All builds are have not reference to web anymore
 Added (Moq): Support for for strict mocks
-Added (Moq): The MockRepository can be accessed using kernel.MockRepository  
+Added (Moq): The MockRepository can be accessed using kernel.MockRepository