Add `basic_quorum` and `notfound_ok` request options on get.

I originally set out to investigate the deletedvclock issue in #332,
but discovered that these quorum parameters were missing.
Add check that the request actually succeeds and returns missing object.
Merge pull request #353 from basho/bugfix/missing-quorum-params

Add basic_quorum and notfound_ok request options on get.

Reviewed-by: javajolt