better handling of whoosh initialization
keep the order of Bookmarks in by_id()

By keeping the order in by_id() we can leverage the sorting of the
results from Whoosh queries.
fix submit_by_day() compatibility handler
polish some search code
reintroduce Alembic support
Removed Flask-SQLAlchemy and did some minor model refactoring.

Flask-SQLAlchemy is nice but it gets in the way so I decided to revert
to plain SQLAlchemy; this is also needed for the future implementation
of the search engine.
import pagination from Flask-SQLAlchemy
implements the backend of the search engine
remove unused field from whoosh schema
more db refactoring
removed OpenID support as it wasn't needed
import db code left behind
bump version to 0.1.19
better handling of Tag deletion
correct logging in mail delivery class
add backup command
add import command
correct commit on whoosh interface
admin panel correction
fix importer script