ACCUMULO-2170 Update CHANGES for 1.5.1 from jira.
Merge branch '1.5.1-SNAPSHOT' into 1.6.0-SNAPSHOT

Conflicts:
	CHANGES
ACCUMULO-1930 Adding StatsCombiner and Classpath test
ACCUMULO-2317 fixing shell
ACCUMULO-2060 Jars which are expected to be reloaded should go in lib/ext, not lib
ACCUMULO-2283 removing server-extras