lib/validators: Added FieldFieldValidator for werkzeug file uploads
flask: Converted /flights/upload from tg to flask
views/flights: Cleanup
views: Use url_for for base redirection
views/i18n: Cache list of translations on startup
views/notifications: Removed app dependency
flask: Converted /flights/<id> from tg to flask
views: Converted /flights/<id>/near route
views: Converted /flights/<id>/change_pilot route