Improve logging for Logminer adapter

The following logging improvements would greatly help debugging user issues w/Logminer:

1. Indicate if data dictionary is being built inline
2. Indicate if flush table is being written to and with what value
3. Indicate mining session arguments (start/end scn, strategy, continuous mining)
4. Fix database time logging to indicate difference with connector system time
5. Indicate when transaction buffer is empty and offset scn is being updated
6. Indicate when transaction buffer largest scn is being updated