Fix nuxeo-tag overflow in nuxeo-data-table-cell

When a Document's Directory-based property is set with a large number of items (e.g. 5+), the data table cell displaying these items using nuxeo-tag elements overflows on the right side, making it impossible to view all items.

Steps to Reproduce:

1. In Nuxeo Web UI, create or edit a Document with a Directory-based property (e.g. dc:subjects) to have 5+ items.
2. In the Document's containing Folderish, display the column corresponding to this property.

Expected result: All nuxeo-tag elements or their content are able to be viewed from the data table cell - either by increasing row height to accomodate all tags, or providing an ellipses able to open a dialog showing all tags, or another means.

Actual result: nuxeo-tag elements are cut off at the right side of their containing nuxeo-data-table-cell, preventing all tags from being seen.

Attaching visual demonstrating issue for reference.