Change dump method for Aggregated Exceptions (and corresponding unit test)
Added & fix comments

- Version 2.8.13 support of  AggregatedException in ActivityLogger.
Merge branch 'develop'
Minor enhancements.

- Util.BinarySearch works on IReadOnlyList.
- Test code coverage increased.
- Comments.
Version 2.8.14
Merge commit '2eef83cc7d1709d40f94b2afc269b21535b105bc'