Planner logging improvements

In planner, there is some inconsistency on how index information is logged. E.g., replica repair logs the instance ID while the plan logs the index name. PopulateAlternateShardIds() log the index name, index definition ID. 

It is not possible to trace the complete lifecycle of an index during the plan phase with a single Regex. The aim of this ticket is to make logging in planner uniform so that it becomes easy to debug.

This is more of a continuous effort but we can start with this ticket to improve logging to a significant extant.