support supplying hooks when opening connections (fixes #3)

To support setting SQLite pragmas when opening a connection, we add the following:

1. 2 new functions added: openWith and createSqlitePoolWith. Which will receive a connection string and an additional parameter: [SQL], to execute after establishing a connection.
2. A change to createSqlitePool - will, by default, set the busy_timeout to 30000 ms, to avoid "database locked" errors, and will set the "foreign_keys" to true, to enforce foreign key constraints.