This is preparation for fixing IMPALA-97. These changes are mostly
non-functional to bring the code closer to styling standards.
The biggest functional changes should be:
1) IMPALA-1623 was caused by a misuse of a constructor and that code
didn't compile after the refactor so the bug was fixed.
2) TimestampValue.Hash() seems to have been hashing the time twice
instead of the time and date.
3) Timings using TimestampValue.time() would not be accurate when
crossing midnight (time and date are separate fields).
4) Timings using local time should use UTC to avoid daylight savings
problems.
5) Use system monotonic clock in util/time.h.
Some timings may still be affected by #3 & 4 above but fixing those
isn't the purpose of this change.
Change-Id: I26056c876c4361e898acc3656aa98abf6f153a6b
Reviewed-on: http://gerrit.sjc.cloudera.com:8080/5779
Reviewed-by: Casey Ching <casey@cloudera.com>
Tested-by: jenkins
fd09294b74