ACCUMULO-1312 use Credentials object to avoid serializing as long as
possible
ACCUMULO-1312 Fix mapred and proxy serialization issues.
ACCUMULO-1565 applying Sean Hickey's patch
Merge branch 'master' of https://git-wip-us.apache.org/repos/asf/accumulo
ACCUMULO-1312 Test Connectors and serialization with destroyed tokens
Merge remote-tracking branch 'asf/master' into ACCUMULO-1496

Conflicts:
	core/src/main/java/org/apache/accumulo/core/util/CreateToken.java
	server/src/main/java/org/apache/accumulo/server/util/Admin.java
ACCUMULO-1496 Fix merge bug