Add feature to pause-stop WHM backup process

As a systems administrator, I would like the ability to cancel or pause a backup in progress without creating orphan folders in /backup, so that if needed, I can prioritize CPU to more important tasks if necessary.

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I, as a sysadmin, have found myself in the need to forcefully kill backup processes (backup, pigz, pkgacct...) several times in order to do any other more urgent and cpu intensive admin task. Killing backup processes can't be adviced, but it could be avoided if we could go to a Backup screen where you can see the progress and be able to pause the process, or even completely abort it without leaving orphan folders within /backup.

I hope you can take this into consideration as it could be very beneficial.

Thank you!