Clarify Single-statement Multirow Inserts

[dclements]

<none> [2] > create database test
created database test
<none> [3] > use database test
switched to database test
test [4] > create table test (id int32, val int32, primary key (id))
table test defined
test [5] > insert into test values (1, 1), (2, 3), (5, 8)
inserted 1 row
test [6] > select * from test
    inserted    1   1

test [7] > 

I'd expect one of two behaviors here:

1. Behave like the PostgreSQL's multirow VALUES and insert all three items.
2. Return an error indicating that the input was not understood.