data migrations for ver2 of the site

We need to move some data around before we can deploy the new site. Running this now won't affect the current site it will just create the new ShogunPage model  and add another foreign key to articles. The second script will populate the ShogunPages table by copying the old data into the new structure and fill in the new foreign key field of article. 

The old data is left in tact here, it can be removed with a future task. 

run evolutions
  ./manage syncdb
  ./manage evolve --execute
run command
  ./manage convert_all_subpages