RFR: 7039: Timestamp granularity too coarse

[Suchita Chaturvedi]

As part of this enhancement request, user can see the timestamps down to fraction of a second.
This will solve the problem for all views, including Event Browser, Properties where most of the records are differentiated by fraction of seconds but since the timestamp shown is only till second, the difference is not visible on UI.

For ex: If the End Time of Event is listed as below, the difference is clearly visible
![image](https://user-images.githubusercontent.com/11155712/105097851-465a8680-5acf-11eb-8a5c-f01ecb3390ce.png)

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Commit messages:
 - 7039: Timestamp granularity too coarse

Changes: https://git.openjdk.java.net/jmc/pull/201/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jmc&pr=201&range=00
  Issue: https://bugs.openjdk.java.net/browse/JMC-7039
  Stats: 10 lines in 2 files changed: 3 ins; 0 del; 7 mod
  Patch: https://git.openjdk.java.net/jmc/pull/201.diff
  Fetch: git fetch https://git.openjdk.java.net/jmc pull/201/head:pull/201

PR: https://git.openjdk.java.net/jmc/pull/201