Made hiding widgets for guests/registered sensible.
better check
Merge pull request #2328 from dwendt/master

Made hiding widgets for guests/registered sensible.
error check
closes #2303

see
https://community.nodebb.org/topic/3039/filter-post-parse-and-filter-post-parsesignature-changes
closes #2248
closes #2297
if sigs are disabled, actually disable them
updating markdown and mentions minvers
dont display email/fullname if they are private
filter:user.account
removing unnecessary markup
closes #2339