RFR: 7091: JOverflow Instance View table should be sortable by clicking headers

[Marcus Hirt]

On Fri, 15 Oct 2021 20:07:47 GMT, Alex Macdonald <aptmac at openjdk.org> wrote:

> This PR addresses JMC-7091 [[0]](https://bugs.openjdk.java.net/browse/JMC-7091), in which the tree viewer in the JOverflow instances tab does not allow the table to be sorted via the column headers. Currently the viewer column headers do not perform any action when clicked. Now a comparator have been added to the viewer which sorts based on the column header (String comparison for the Name & Value columns, Integer for the Size column).
> 
> Screenshot:
> ![2021-10-14-142941_1074x516_scrot](https://user-images.githubusercontent.com/10425301/137375980-daa9e849-5aec-41c8-9cb5-00104a15e682.png)
> 
> Gif:
> ![7091](https://user-images.githubusercontent.com/10425301/137375958-a9186bf8-36ea-43e3-91b5-ee85aaca9037.gif)
> 
> [0] https://bugs.openjdk.java.net/browse/JMC-7091

Marked as reviewed by hirt (Lead).

-------------

PR: https://git.openjdk.java.net/jmc/pull/322