Add model for Talk
Add talk list page view
Make scrapping failures explicit

Also added a test case for the parser.
Add tagged talk list view
Add tests for views
Refine image scrapping logic
Fix errors when certain pages does not exist.

Also added some comments to clear up the logic.

Cherry-picked from f65eda5 (master)
Merge branch 'talks'
Tweak dashboard to group things together
Refactor fabfile and add migrate task