ACCUMULO-2764 Wrap the MAC process termination in a Callable to get timeout semantics
Merge branch '1.5.2-SNAPSHOT' into 1.6.1-SNAPSHOT

Conflicts:
	minicluster/src/main/java/org/apache/accumulo/minicluster/MiniAccumuloCluster.java
Merge branch '1.6.1-SNAPSHOT' of https://git-wip-us.apache.org/repos/asf/accumulo into 1.6.1-SNAPSHOT
Merge branch '1.6.1-SNAPSHOT' of https://git-wip-us.apache.org/repos/asf/accumulo into 1.6.1-SNAPSHOT