Investigate improving fetching column qualifiers

This may need to be an Accumulo issue, after investigation is done. Fluo uses Accumulo scanners and batch scanners and calls fetch column passing a cf and cq. I think the implementation will scan between col quals. Would be nice if it eventually seeked.

Start by tracing how Fluo uses Accumulo scanners and batch scanners when fetching a column with a column family and column qualifier. Compare the current behavior of scanning between column qualifiers with the desired seek behavior, then determine whether the needed change belongs in Fluo or should be raised as an Accumulo issue.

Written by the indexing model from the issue text.