Do not store Accept-language full string, only store one detected language fixes #5365
Merge branch 'bugfix/5365' of github.com:piwik/piwik into bugfix/5365
Introduce new function and tests to make it clearer what's happening #5365
Merge pull request #6657 from piwik/bugfix/5365

 Do not store Accept-language full string, only store one detected language