Remove email, phone, im records when data is deleted and update is_primary

Current behavior:

• A contact's location has 2 emails (or phones or im's), and the email address is cleared by user on the 'primary' (1st) email during an Edit (update).

• This results in NULL value in crm_email.email column (or crm_phone/im) on the primary email (phone, im).

Desired behavior:

• When the significant data field is cleared, that record should be deleted (empty crm_email.email = delete that crm_email record, crm_phone.phone..., crm_im.name...).

• If the record being deleted WAS the primary class instance for that location (is_primary = TRUE), AND there is another instance of that class associated with that location, the 'next' instance should become primary (e.g. .is_primary set to TRUE) (get 'next' by table PK).