bugfix: disallow messages with empty subject-header
Merge branch 'master' of https://github.com/jungepiraten/nntpboard
Merge branch 'master' into jupis

Conflicts:
	classes/template/smarty/templates/header.html.tpl
Merge branch 'jupis' of https://github.com/jungepiraten/nntpboard into jupis

Conflicts:
	classes/template/smarty/templates/header.html.tpl