Our spk currently have an issue with the bundled MongoDB (forked)
version that breaks if some files are inserted in a GridFS collection.
We need to find out a way to upgrade and migrate the bundled database
until we can re-enable the attachment feature.
Note that the feature is unmodified, it's just hidden in the UI.
This new draft saving system is currently only implemented for the
card description and comment. We need better a component
inheritance/composition model to support this for all editable fields.
Fixes#186