add handlers for the newly added page
add method for refresh douban token when it expires; but it may not work? at least it could delete the token in datastore so user would be notified to grant again
add utf8 encoding for comment/tags while syncing a book
set limit of comment to be max: 350 characters
can choose to disconnect from douban now; auth douban in a new tab
format some coding style according to sublime's linter
remove imports in pages/__init__.py
remove extra imports in books/__init__.py
remove extra imports in utils/__init__.py
remove previous debugging tags