Update changelog for 0.21 release

Author: Rpinski

backend/ILSpy-backend.sln

@@ -12,6 +12,8 @@ Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "Solution Items", "Solution
 		LICENSE.TXT = LICENSE.TXT
 		README.md = README.md
 		..\README.md = ..\README.md
+		..\vscode-extension\CHANGELOG.md = ..\vscode-extension\CHANGELOG.md
+		..\GitVersion.yml = ..\GitVersion.yml
 	EndProjectSection
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "TestAssembly", "TestAssembly\TestAssembly.csproj", "{98030DE1-DC87-4E74-8201-FE8E93E826B5}"

vscode-extension/CHANGELOG.md

@@ -2,6 +2,10 @@
 
 All notable changes to the "ilspy-vscode" extension will be documented in this file.
 
+## 0.21
+
+- Upgrade to ICSharpCode.Decompiler 9.1 (see release notes for [ILSpy 9.1](https://github.com/icsharpcode/ILSpy/releases/tag/v9.1) to get more details)
+
 ## 0.20
 
 - Introduction of "Analyze" feature similar to ILSpy desktop application: You can analyze where a method is called, a type is used or an interface is implemented. See [Wiki](https://github.com/icsharpcode/ilspy-vscode/wiki/Analyze) for a description.