fix case-sensitivity bug with SQL CASE/ELSE clause

[mccanne]

No description provided.

[philrz]

Verified in super commit 5c1851b.

Before:

$ super -version
Version: v1.18.0-155-g5f18349a

$ super -c "
SELECT OrderID, Quantity,
CASE
    WHEN Quantity > 30 THEN 'The quantity is greater than 30'
    WHEN Quantity = 30 THEN 'The quantity is 30'
    ELSE 'The quantity is under 30'
END AS QuantityText
FROM order_details.csv;"
parse error at line 6, column 5:
    ELSE 'The quantity is under 30'
=== ^ ===

Now:

$ super -version
Version: v1.18.0-157-g5c1851be

$ super -c "
SELECT OrderID, Quantity,
CASE
    WHEN Quantity > 30 THEN 'The quantity is greater than 30'
    WHEN Quantity = 30 THEN 'The quantity is 30'
    ELSE 'The quantity is under 30'
END AS QuantityText
FROM order_details.csv;"

{OrderID:10248.,Quantity:12.,QuantityText:"The quantity is under 30"}
{OrderID:10248.,Quantity:10.,QuantityText:"The quantity is under 30"}
...
{OrderID:10443.,Quantity:12.,QuantityText:"The quantity is under 30"}

Thanks @mccanne!