ACCUMULO-2443: Change README of auto test to say tool.sh instead of accumulo

Signed-off-by: Sean Busbey <busbey@cloudera.com>
Merge branch '1.5.2-SNAPSHOT' into 1.6.1-SNAPSHOT

-s ours, only change was README for test that don't exist.
Merge branch '1.6.1-SNAPSHOT'