ACCUMULO-3181 VolumeChooser usage doesn't always comply with implied API contract

Signed-off-by: Sean Busbey <busbey@cloudera.com>
Merge branch '1.6'

Conflicts:
	server/base/src/main/java/org/apache/accumulo/server/init/Initialize.java
	server/base/src/main/java/org/apache/accumulo/server/util/MetadataTableUtil.java