From the documentation:
How to contribute
Install the NETFx Contributor VSIX from the Extension Manager.
Restart VS, and now you’ll get the NETFx Extension template:
Things to note:
- The Location MUST be under the netfx\Extensions folder
- The directory structure following Extensions is used to make up your extension id, in the above case, it will be “netfx-System.Net.Http.HttpResponseExtensions”
- UNCHECK the “Create directory for solution” option, or otherwise you’ll end up with a duplicate name in the package ID and the folder structure. If you make this mistake (I do it all the time ...