Adding news, a logo and GitLab-header files, and cleanups.

_includes/JLUGitLabheader.png

_includes/JLUGitLablogo.png

_includes/header_master.svg

_includes/logo_master.svg

de_about.md

de_help.md

de_news.html

de_termsofservice.md

en_about.md

en_help.md

en_news.html

en_termsofservice.md