Bad seeds cause segfault in EuDX

This is more of an issue than a pull request, but I wanted to include a test to demonstrate the issue. This test causes a segfault on my machine.

I don't even want to tell you guys how long it took me to track this one down :). For most of the day I thought it was my streamlines example that was causing the segfault (which it kind of was because it was passing bad seeds to eudx), but because "in the wild" my seed points we're this extremely bad, I mostly just got funny behavior and intermittent segfaults so I couldn't tell where the issue was. Anyways I digress.