Add option sqlite_debug_show_queries to print queries sent to SQLite

[noahisaksen]

Implements issue#122

Name	Description	Default
sqlite_debug_show_queries	DEBUG SETTING: print all queries sent to SQLite to stdout	false

Implemented like the postgres_scanner and mysql_scanner this PR adds the setting, sqlite_debug_show_queries which prints the queries sent to sqlite to stdout using the helper Printer.

I don't believe we are able to test the stdout output in the sqllogictests, so I made sure to at least have a test that shows that enabling this setting, does not break regular queries.

Sample output.

D load 'build/release/extension/sqlite_scanner/sqlite_scanner.duckdb_extension';
D SET sqlite_debug_show_queries=true;
D ATTACH 'data/db/sakila.db' AS sakila;
D SELECT * FROM sakila.store limit 1;
BEGIN TRANSACTION

SELECT type FROM sqlite_master WHERE lower(name)=lower('store');

PRAGMA table_info('store')

SELECT MIN(ROWID), MAX(ROWID) FROM "store"

COMMIT

BEGIN TRANSACTION

SELECT type FROM sqlite_master WHERE lower(name)=lower('store');

PRAGMA table_info('store')

SELECT MIN(ROWID), MAX(ROWID) FROM "store"

SELECT "store_id", "manager_staff_id", "address_id", "last_update" FROM "store" WHERE ROWID BETWEEN 0 AND 2

COMMIT
┌──────────┬──────────────────┬────────────┬─────────────────────┐
│ store_id │ manager_staff_id │ address_id │     last_update     │
│  int64   │      int64       │   int64    │      timestamp      │
├──────────┼──────────────────┼────────────┼─────────────────────┤
│        1 │                1 │          1 │ 2021-03-06 15:52:00 │
└──────────┴──────────────────┴────────────┴─────────────────────┘