DDL for LookupValue

[darnjo]

The lookup value table is a bridge between fields and lookups for a given resource record.

Create a table that contains the following items:

• LookupValueKey
• ResourceName
• ResourceRecordKey
• FieldName
• LookupKey
• ModificationTimestamp

Then, until #76 is merged, we can use a test record with Property (ListingKey, ListPrice, ModificationTimestamp) and a multi-lookup value (ExteriorFeatures) to ensure this functionality works correctly.