Make sure sufficient VDBE registers are allocated for an INSERT...SELECT
when there is an idlist on the insert table that includes an explicit
rowid.  Ticket [9654505cfda93610585fde5a9bbf2e730c8a8d5]
In the command-line shell, if three or more interrupt signals (control-c)
are received in a row without a response from sqlite3_interrupt() then
call exit(1) immediately.  This allows control-C to interrupt the shell
even if it is stuck in a computation or loop that does not involve the
VDBE.
Changes to the output of EXPLAIN QUERY PLAN to make it clearer when a query uses the PRIMARY KEY index of a WITHOUT ROWID table.