SMF Error's during clean SQLite3 install (#1740)

Added check for if the $handle is a object
Update Subs-Db-sqlite3.php

Removed new line
Update Subs-Db-sqlite3.php

Added closing tag back
Update Subs-Db-sqlite3.php
Update Subs-Db-sqlite3.php
Merge pull request #1756 from tinoest/release-2.1

SMF Error's during clean SQLite3 install (#1740)