message: Update CHANGELOG date for 1.13.0
diff: * There currently is no completion support for package references in csproj files. ([#1156](https://github.com/OmniSharp/omnisharp-vscode/issues/1156))
  * As an alternative, consider installing the [MSBuild Project Tools](https://marketplace.visualstudio.com/items?itemName=tintoy.msbuild-project-tools) extension by @tintoy.
  -## 1.13.0 _(Not Yet Released)_
  +## 1.13.0 (November 7, 2017)
  #### Cake
  