- add test create story and create post - create story test can reproduce the bug that stories does not show up on the 'Your Pages' tab in profile page

Repro steps:
1. create a story
2. be redirected to profile page
3. click on 'Your Pages' tag

observed:
- You have not created any pages yet.

expected:
- newly created Story
- add django-nose for development environment
- add tests for PostForm