CBQE-2146: Improved test log directory structure as
logs/testrunner-<timestamp>/test-<case_number>/test.log and
logs/testrunner-<timestamp>/test-<case_number>/test.logging.conf and all
diag logs and related cbcollectinfo will be collected in this folder
only

Change-Id: I0e9c3730cefcdea203859117b4c6d06fde7669ad
Reviewed-on: http://review.couchbase.org/34918
Tested-by: buildbot <build@couchbase.com>
Reviewed-by: Sangharsh Agarwal <sangharsh.agarwal@globallogic.com>
Tested-by: Sangharsh Agarwal <sangharsh.agarwal@globallogic.com>