Remove unsafe directive to xentral.com etc.

[OpenXE-ERP]

<meta http-equiv="Content-Security-Policy" content="default-src 'self' 'unsafe-inline' 'unsafe-eval' xentral.com *.xentral.com xentral.biz *.xentral.biz *.wawision.de *.embedded-projects.net maps.googleapis.com maps.gstatic.com www.youtube.com thumbs.ebaystatic.com ;">