Get end to end tests to work with TravisCI

[JesseRWeigel]

The problem right now is has to do with running chrome as a headless browser. I can get it running (see the commented out lines in travis.yml), but I think the tests themselves are trying to start chrome too. Travis is not allowing this. This is the error message:

> mocha --timeout 30000 ./e2e/runner.js ./e2e/tests/*.spec.js
(node:4772) UnhandledPromiseRejectionWarning: Error: Failed to launch chrome!
[4782:4782:0327/230654.509917:FATAL:zygote_host_impl_linux.cc(126)] No usable sandbox! Update your kernel or see https://chromium.googlesource.com/chromium/src/+/master/docs/linux_suid_sandbox_development.md for more information on developing with the SUID sandbox. If you want to live dangerously and need an immediate workaround, you can try using --no-sandbox.