Session management system

- Managers bound to the session instead of to Torch
- TorchSession automatic creation and destruction
- Automatic manager creation for sessions

Torch.API/Torch.API.csproj

@@ -175,6 +175,7 @@
     <Compile Include="Properties\AssemblyInfo.cs" />
     <Compile Include="ServerState.cs" />
     <Compile Include="ModAPI\TorchAPI.cs" />
+    <Compile Include="Session\ITorchSession.cs" />
   </ItemGroup>
   <ItemGroup>
     <None Include="packages.config" />