Modifying template for compatibility with DataTables. When no rows are a...

Modifying template for compatibility with DataTables. When no rows are available, simply do not display the table (it's not needed anyway). DataTables is expecting the number of column headings to match the number of columns in each row, rather than calculating rows that might be set via "colspan".

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | -
| Refs tickets  | -
| License       | MIT
| Doc PR        | -