Add onColumnResizerClick and onColumnResizerDoubleClick callbacks for column resizers on DataTable

[master117]

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[ ] bug report
[x] feature request
[ ] support request => Please do not submit support request here, instead see https://forum.primefaces.org/viewforum.php?f=57

I would like to have click and double click events for column resizers. Many DataTable tools feature (double)click between table headers for automatic column width adjustment. Like excel, google docs etc. To be able to add this functionality I need to receive click events from the resizer.