mobile private post dont show error 404
fix missing indent for correct header container relative positions
Update Changelog.md
fix mentions at the end of a post
Merge pull request #4150 from svbergerem/3746-fix-mentions

fix mentions at the end of a post
Merge branch 'patch-2' of git://github.com/rivendale2010/diaspora into develop

Conflicts:
	Changelog.md
	app/views/layouts/_header.html.haml
Merge branch 'error_404_mobile' of git://github.com/movilla/diaspora into movilla-error_404_mobile

Conflicts:
	Changelog.md
404, not 500, if  signed out user wants to see a non public/existing post

Also add some specs for Post#find_by_guid_or_id_with_user