TFS Policy Extension Doesn't run in 2015

I've created a TFS Policy extension. This project works fine when installed into VS2013, but when I try to run it, it fails to execute correctly. 

I have a RegistryKey.pkgdef file present, which contains the following code

[$RootKey$\TeamFoundation\SourceControl\Checkin Policies]"NOCOMMIT.Tfs.Policy"="$PackageFolder$\NOCOMMIT.Tfs.Policy.dll"

My vsixmanifest is also set up with (what I believe) is the correct settings:

<?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="1041BDE4-EA42-422F-AB59-6D3659265DE4" Version="0.1" Language="en-US" Publisher="Obsidian Phoenix" /><DisplayName>NoCommit.Tfs.Policy</DisplayName><Description>Prevents committing if any NOCOMMIT comments are found in the checked out files.</Description></Metadata><Installation InstalledByMsi="false"><InstallationTarget Id="Microsoft.VisualStudio.Pro" Version="[12.0,14.0]" /><InstallationTarget Version="[12.0,14.0]" Id="Microsoft.VisualStudio.Premium" /><InstallationTarget Version="[12.0,14.0]" Id="Microsoft.VisualStudio.Ultimate" /></Installation><Dependencies><Dependency Id="Microsoft.Framework.NDP" DisplayName="Microsoft .NET Framework" d:Source="Manual" Version="[4.5,)" /></Dependencies><Assets><Asset Type="Microsoft.VisualStudio.VsPackage" d:Source="Project" d:ProjectName="%CurrentProject%" Path="|%CurrentProject%;PkgdefProjectOutputGroup|" /><Asset Type="Microsoft.VisualStudio.VsPackage" d:Source="File" Path="RegistryKey.pkgdef" /></Assets></PackageManifest>

When debugging in the experimental instance, the extension is installed, but All I get in the Pending Changes window is:

Internal error in NoCommit Policy for Visual Studio. Error loading the NoCommit Policy for Visual Studio policy (The policy assembly is not registered.). 

I also have this problem when attempting to update the VersonOneTFS Policy (It's not my repo, but I was attempting to update it to support the latest VS).

What step am I missing to be able to use this policy in VS2015?