Keep track of offset when performing search in SearchRecord

When we skip a stop word, we must record an offset so that we can
correctly determine if the next match is in the correct position
relative to the last term match
Do not force abort for AtomicOperation if write fails

After thinking about this, it seems that there is no reason to
force abort if the write fails because A) we return a boolean to notify
the caller that the write fail and B) no data is altered in the atomic
operation or the destination store, so its harmless