updates column visibility to use accumulo access library

[keith-turner]

Updates ColumnVisibility and VisibilityEvaluator to use the Accumulo Access control library :

https://github.com/apache/accumulo-access

This library is not yet released, so building requires installing it locally.

[dlmarion]

If org.apache.accumulo.access.Authorizations.EMPTY is not made public in apache/accumulo-access#70, then we should get a reference to an empty authorizations object and return it here instead of calling Set.of here. Considering this is called from the VisibilityFilter, we should make this as optimized as possible.

[keith-turner]

Looking at the impl of Set.of() in my ide it does not allocate any objects, it always returns a statically initialized immutable empty set. Then with the eventual changes in accumulo-access this line will do no obj allocations, however it does that in a very round about way.

Should probably add a Authorizations.of() method to follow javas conventions. Also would make it consistent w/ AccessExpression.of(). If Authorizations.of() existed then this could be more straightforward.

[keith-turner]

Added a constant iin 5b825ab, seemed the best options w/ the current constraints of the beta API. Can easily change it later.

[dlmarion]

I added accumulo-access to the ASF Jenkins (https://ci-builds.apache.org/job/Accumulo/job/Accumulo-Access-main) which should push the built jars into the snapshot repo. I'm wondering if that's enough to change the dependency from 1.0.0-beta to 1.0.0-SNAPSHOT as there have been changes since the beta release. It doesn't look like it's building reliably, but I just kicked a build off.

Update: Build finished, new snapshot artifacts at https://repository.apache.org/content/repositories/snapshots/org/apache/accumulo/accumulo-access/1.0.0-SNAPSHOT/.

Update #2: Since Accumulo's parent pom is the Apache Parent POM, we don't need to do anything to reference snapshot releases in the ASF repo. It's already included in the Parent POM.