Using null instead of empty strings

[konklone]

In general, using null instead of "" will be semantically more clear in communicating when there is no value for a field, versus when the value for a field is an empty string.

For example, if a legislator has no YouTube account, the value should ideally be null instead of "".

[dwillis]

Working on this.

[dwillis]

This is mostly done and in the API now. Will review the remaining responses and update as needed.

[konklone]

Flagging: the meeting_type and url fields on the hearings endpoint use empty strings instead of nulls.

[konklone]

Flagging: the action_id field on (Senate) floor updates uses empty strings instead of nulls.

[konklone]

Flagging: the tie_breaker and tie_breaker_vote fields on Senate votes are empty strings instead of nulls when no tie breaking vote took place.

[konklone]

Flagging: committee memberships have a couple of empty string fields:

                 "note": "",
                 "begin_date":""

[konklone]

Flagging: times_topics_url fields on legislators have empty strings.

[konklone]

Flagging: I've found an empty string used for middle_name on legislators (see Edward Royce for an example).

[dwillis]

Will fix.