Refactoring minicluster files to remove 1 TODO

[Amemeda]

Refactoring group of minicluster files into server.base.src.main.java.org.apache.accumulo.server.cluster

[Amemeda]

This resolves 1 TODO from #2699

[ctubbsii]

The weird thing about these ones is that these classes are supposed to represent a generic cluster, not specifically a minicluster (which is one specific instance of a cluster). So, I'm not sure it makes sense to move them into the minicluster package (which is listed as public API). If possible, it might make sense to move them into the server base jar instead of the minicluster jar, with a package name like org.apache.accumulo.server.cluster, that is not public API.

[Amemeda]

The weird thing about these ones is that these classes are supposed to represent a generic cluster, not specifically a minicluster (which is one specific instance of a cluster). So, I'm not sure it makes sense to move them into the minicluster package (which is listed as public API). If possible, it might make sense to move them into the server base jar instead of the minicluster jar, with a package name like org.apache.accumulo.server.cluster, that is not public API.

would the rest of the files in minicluster and miniclusterImpl have to move to the new package as well?