Fix XSS issue in poll questions

closes #5274
Merge branch 'hotfix/0.4.1.1' into develop

Conflicts:
	Changelog.md
	config/defaults.yml
Fix services in statistics.json.
Currently there is a bug in configurate that reports incorrectly the services settings if they are set as ENV variables, instead of diaspora.yml settings.
This commit works around that issue by changing the way the setting is fetched.
Fix statistics_presenter_spec