Tag selenium test as developing

We are not yet finished with the test, which causes a failure in CI.  Thus
we tag it as developing so it can be excluded as a critical test with the
following PyBot command:

    pybot -n developing check_website_links.txt
Begin ignoring files generated by Robot Framework

These include: log.html, output.xml, and report.html.  These are generated
and updated on each RF run, and thus should not be committed into Git.
Merge branch 'master' of https://github.com/basvodde/scrumprimer