Anonymous user can get Create Article page by direct link

Anonymous user can see Write Article page by direct link .

How to reproduce:

1. Log out if you was logged in
2. Open Create Article page.

Actual result: Create Article page is opened
Expected result: user is redirected to sign in page; access should be denied to Write Article page for anonymous user.

Note several results of this issue:

1. When user changes tab to Preview Article, he sees message "Please login first to create article previews". When user is back to first tab, message duplicates and he sees "Please login first to create article previewsPlease login first to create article previews"
2. If user writes Article and logs in, he loses all text.