Help updating package to 2015

I recently installed Visual Studio 2015 Enterprise and I wanted to convert my open source package Regionizer (http://regionizer.codeplex.com) to work on 2015.

I tried using the original extension.manifest and was told in another post that things have changed for 2015.

I created a new project just to see the new format, and tried copying it to use.

Here is the new manifest:

<?xml version="1.0" encoding="utf-8"?><PackageManifest Version="2.0.0" xmlns="http://schemas.microsoft.com/developer/vsx-schema/2011" xmlns:d="http://schemas.microsoft.com/developer/vsx-schema-design/2011"><Metadata><Identity Id="91a3b3a1-be96-4b39-8b07-a99832fb4d2e" Version="2.2" Language="en-US" Publisher="Data Juggler" /><DisplayName>Regionizer</DisplayName><Description>An advanced C# document formatter.</Description><License>Regionizer License Terms.rtf</License><Icon>RAD Studio Icon.ico</Icon><PreviewImage>Regionizer Image Preview.png</PreviewImage></Metadata><Installation><InstallationTarget Id="Microsoft.VisualStudio.Community" Version="[14.0]" /><InstallationTarget Version="[14.0,15.0)" Id="Microsoft.VisualStudio.Pro" /><InstallationTarget Version="[14.0,15.0)" Id="Microsoft.VisualStudio.Enterprise" /></Installation><Dependencies><Dependency Id="Microsoft.Framework.NDP" DisplayName="Microsoft .NET Framework" d:Source="Manual" Version="[4.5,)" /><Dependency Id="Microsoft.VisualStudio.MPF.14.0" DisplayName="Visual Studio MPF 14.0" d:Source="Installed" Version="[14.0]" /></Dependencies><Assets><Asset Type="Microsoft.VisualStudio.VsPackage" d:Source="Project" d:ProjectName="%CurrentProject%" Path="|%CurrentProject%;PkgdefProjectOutputGroup|" /></Assets></PackageManifest>

If I run the project in Debug mode it works, the package is available under the Tools menu and it looks like all is good.

When I click on the Regionizer.vsix that is generated, nothing happens.

How to I debug why nothing happened, and also, do I have to have separate packages to run in VS 2012 and VS 2013, and one to run in VS 2015?

Thank you for any help, I am stuck.

If anyone can get the version on the open source site working on 2015 (and 2012 and 2013 is a plus) please let me know what I have to do; I haven't made any code changes, I just want this to run in 2015.