ACCUMULO-2476, ACCUMULO-2342 Sleep after we modify a constraint. -- cherry-picked d4b06999 back to 1.4
Merge branch '1.4.5-SNAPSHOT' into 1.5.2-SNAPSHOT
Merge branch '1.5.2-SNAPSHOT' into 1.6.0-SNAPSHOT

Conflicts:
	proxy/src/test/java/org/apache/accumulo/proxy/SimpleProxyIT.java