Update the DSN constant to support PDO

Per #253.
Replace the MDB2 connection with a PDO connection

Per #253.
Replace all MDB2 code with PDO code

Per #253.
Replace all MDB2 code with PDO code

Per #253.
Fix PDO::rowCount()

Per #253.
Replace all MDB2 code with PDO code

Per #253.
Quiet PHP_NOTICE by establishing $sidebar
Add comments
Be more cautious before using optional fields
Suppress PHP_NOTICE by using empty()
Rewrap comments
Replace all MDB2 code with PDO code

Per #253.
Merge pull request #279 from statedecoded/PDO

Replace MDB2 with PDO