Adding CleanZookeeper utility to accumulo admin command

[cshannon]

Found another utility that can be moved to the accumulo admin command. This utility cleans all old instances out of Zookeeper (except the current one). It's a bit different than the DeleteZooInstance command as that command allows deleting a single instance that is specified so it's worth having both.

This is a follow on to #2807

[dlmarion]

Small nit, LGTM

[cshannon]

@milleruntime - Any thoughts on this before merging since you looked at the others?

[milleruntime]

This looks good but #2914 is a priority and they both touch Admin.

[ctubbsii]

Found another utility that can be moved to the accumulo admin command. This utility cleans all old instances out of Zookeeper (except the current one). It's a bit different than the DeleteZooInstance command as that command allows deleting a single instance that is specified so it's worth having both.

I'm not sure it's worth having both. The delete one could just have a flag to delete all non-current ones.

[cshannon]

Found another utility that can be moved to the accumulo admin command. This utility cleans all old instances out of Zookeeper (except the current one). It's a bit different than the DeleteZooInstance command as that command allows deleting a single instance that is specified so it's worth having both.

I'm not sure it's worth having both. The delete one could just have a flag to delete all non-current ones.

I like that idea, I can simply move this functionality to the other command pretty easily and have a flag as you suggested. Having 1 utility/command to clean up zookeeper instances is probably less confusing and I can just update the troubleshooting documentation.

If no one else has any other comments or objects I can create a new PR tomorrow (and close this one) that moves the functionality here into the other utility and then removes the CleanZookeeper utility as it won't be needed.

[cshannon]

Closing this PR out as I'm going to create a new one and just merge the functionality of CleanZookeeper into the DeleteZooInstance utility with a flag as suggested.