Save a creatorId in the molecule
Save a creatorId in the molecule

This will be the id of the user who created the molecule.

This is done so that one can search for molecules created
by a specific user.

Note that we needed to convert the id to a string, or else
we will not be able to find it by query in self.find()
(unless we convert the creatorId string in the query
to an ObjectId, I think).

Signed-off-by: Patrick Avery <743342299f279e7a8c3ff5eb40671fce3e95f13a@kitware.com>

OpenChemistry/mongochemserver