Possibly make the quarantine_table argument optional in constraint_append

[MrPowers]

constraint_append currently requires a quarantine_table. We may want to allow users to set quarantine_table to None and just throw out the rows that don't match the constraints.

There are probably some users that want to write the bad data to a quarantine table and others that just want to throw out the bad data. Thoughts?

[danielbeach]

@MrPowers I can work on this one if you want.

[robertkossendey]

@danielbeach thank you very much, assigned you! :)