Add Missing Nuget Packages

Author: richard

src/Carter.HtmlNegotiator.csproj

@@ -1,7 +1,16 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
     <TargetFramework>netstandard2.0</TargetFramework>
   </PropertyGroup>
 
+  <ItemGroup>
+    <PackageReference Include="Handlebars.Net" Version="1.9.5" />
+    <PackageReference Include="Microsoft.AspNetCore.Hosting.Abstractions" Version="2.1.1" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\dependencies\Carter\src\Carter.csproj" />
+  </ItemGroup>
+
 </Project>