Update ChangeLog and version for 2.0.0 GA release (#1345)

Author: daxian-dbw

PSReadLine/Changes.txt

@@ -1,3 +1,12 @@
+### Version 2.0.0
+
+Bug fixes:
+
+* Name the `ReadKey` thread for debug purpose (#1313)
+* Compliance: Update the .NET Core version and PowerShell SDK package (#1320)
+* Build: Enable F5 debugging of PSReadLine in Visual Studio (#1319) (Thanks @theaquamarine)
+* Build: Simply the way to get semantic version information in build (#1324)
+
 ### Version 2.0.0-rc2
 
 Pre-release notes:

PSReadLine/PSReadLine.csproj

@@ -6,7 +6,7 @@
     <AssemblyName>Microsoft.PowerShell.PSReadLine2</AssemblyName>
     <AssemblyVersion>2.0.0.0</AssemblyVersion>
     <FileVersion>2.0.0</FileVersion>
-    <InformationalVersion>2.0.0-rc2</InformationalVersion>
+    <InformationalVersion>2.0.0</InformationalVersion>
     <TargetFrameworks>net461;netcoreapp2.1</TargetFrameworks>
   </PropertyGroup>