Added OracleTailor and OracleHaberdashery

Thanks for sharing your work! It really helped me get Dapper working with Oracle.

I added an OracleTailor for the sql string formatting and an OracleHaberdashery class to handle the inserts in an Oracle database using ids
* created by a database trigger (identity = true)
* supplied by user (identity = false)
* supplied by db using a sequence and no trigger (identity = false, SequenceName = "YourSequence")