Basic blog structure (fix #3)

This also intruce webtest.
This also add TimestampedModel in ideasbox models.
action parameter is not needed anymore in HTML5

when submit page is current page
No need to test on len() when using pyquery
Clearner way of testing status codes
fix settings LOGIN_URL value
Use yield_fixture for app fixture
Merge pull request #45 from ideas-box/add-blog

Basic blog structure (fix #3)