igl | cmake | Add a new render session StencilOutlineSession (#349)

Summary:
Added a new render session `StencilOutlineSession`.

Pull Request resolved: #349

Reviewed By: rameshviswanathan

Differential Revision: D94725689

Pulled By: corporateshark

fbshipit-source-id: f064de2858414d5f72ff75bf74caf906209ad9ce

Author: corporateshark

shell/CMakeLists.txt

@@ -123,6 +123,7 @@ if(IGL_WITH_SAMPLES)
   add_shell_session(MRTSession "")
   add_shell_session(MultiDrawIndexedIndirectSession "")
   add_shell_session(ScissorTestSession "")
+  add_shell_session(StencilOutlineSession "")
   add_shell_session(Textured3DCubeSession "")
   add_shell_session(TextureViewSession "")
   add_shell_session(TinyMeshBindGroupSession "")