*Not* security issue: Displays edit view for post regardless of ownership
Steps to reproduce:
1) Create post
2) Copy the link for "Edit Post"
3) Change postid parameter in `http://forum.nim-lang.org/t/<thread_number>?action=edit&postid=<new_post_ID>` to a lower post.

Opens view for editing post; if you try to actually submit changes this will fail if you're not the owner (so not a security issue), but should still fail earlier (and not bring unauthorized user to edit page).
