"My Documents" view broken if an RfcToBe does not have a draft

[jennifer-richards]

If a document assigned to the currently logged-in user does not have a draft associated with it, an error results:

  File "/workspace/rpc/serializers.py", line 134, in get_name
    return rfc_to_be.draft.name
           ^^^^^^^^^^^^^^^^^^^^
AttributeError: 'NoneType' object has no attribute 'name'

This will come up with April 1 RFCs so must be sorted out for that case. It currently comes up with many drafts imported via the (WIP) DB xfer tool, though, and the code needs to handle this possibility better.