Toggle tuple/table output in SQL

[pbailis]

It would be helpful to be able to toggle between tuple and table-level reporting in the SQL console; e.g.,

macrobase-sql> SELECT * FROM DIFF(SPLIT (SELECT *, percentile(battery_drain) AS percentile from mobile) WHERE percentile > .99) ON *;
2 rows

----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|    app_version     |      user_id       |      hw_make       |       state        |  firmware_version  |      support       |    global_ratio    |   outlier_count    |    total_count     |
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|        v50         |         -          |         -          |         -          |         -          |      .873185       |     89.883198      |       902.0        |       1003.0       |
|         -          |         -          |       Emdoor       |         -          |         -          |      .873185       |     89.883198      |       902.0        |       1003.0       |
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
macrobase-sql> \display tuple;
macrobase-sql> SELECT * FROM DIFF(SPLIT (SELECT *, percentile(battery_drain) AS percentile from mobile) WHERE percentile > .99) ON *;
(app_version: 50)
support=.873185, global_ratio=89.883198, outlier_count=902.0, total_count=1003.0

(hw_make: Emdoor)
support=.873185, global_ratio=89.883198, outlier_count=902.0, total_count=1003.0