Feature/example tracer cleanup
We shouldn't require UMFPack since this example is featured in the getting started guide on the website.
The solver commit should be backported to 3.3 (since this is the current stable release).
We shouldn't require UMFPack since this example is featured in the getting started guide on the website.
The solver commit should be backported to 3.3 (since this is the current stable release).