Merge pull request #6 from hkulekci/master

Cooments page sql fix.
UPDATE-fix header(small letter)
UPDATE-add update profile function
UPDATE-add 'edit' function for user's question
UPDATE-fix header.php
UPDATE-add dropdown on nav bar, add sort function according to question's data,rate,total comment
UPDATE- fix pagination
UPDATE-fix login redirect
UPDATE-add twitter bootstap modal(login)