changes creator id to user id
users can create posts and are redirected to post page
Adds post list with authors
Fixes link from post list to single post
fixes minor issues with spec files
Merge branch 'development' of https://github.com/AlexSYanai/zack-overflow into Post-page
merged Post-page and user-page branches
Merge branch 'development' of https://github.com/AlexSYanai/zack-overflow into development