Fixes #11796 E-Mail addresses with special characters are not working by unsanitizing the email address before adding/updating user info. Added tests for several unusual but valid email addresses.
It's annoying that Travis doesn't seem to build some Pull Requests from forks currently. I have pushed the changes of this PR together with latest changes from 4.x-dev into a local branch. So we can see the Travis Build results. See https://app.travis-ci.com/github/matomo-org/matomo/builds/238438467