add field removes prior nodes from table

When a field is added to a content-type after nodes already exist, all existing nodes will not be displayed in flexinode/table/[id] pages.

Steps to reproduce:
1. create a content type with a single field
2. add a node of that content type
3. display the tabular view of the content-type
4. add another field to the content type, as not required, not displayed
5. refresh the tabular view

Expected results: no change

Actual results: the node is dropped from the results

The workaround is to add dummy entries into flexinode_data for the new field.