# Functions
NewDbConnection connects to the reader and writer per passed in options, with retries, returning a DBReaderWriter object that contains sql.DB connection.
NewDbConnectionForTest use this for tests as we have multiple sessions in parallel and don't want the synced one.
NewDbConnectionFromSettings sets up a db connection from the settings, only once.
# Structs
ConnectOptions config options for database.
DB type to wrap sql.DB.
ReaderWriter wraps db reader and writer.
Settings connection settings to postgres db.
Store holds the database connection and other stuff.
Tx type to wrap sql.Tx.