HBASE-12370 Backport IT changes from HBASE-10572 to 0.98
HBASE-11348 Make frequency and sleep times of chaos monkeys configurable (Vandan Ayyalasomayajula)

Conflicts:
	hbase-it/src/test/java/org/apache/hadoop/hbase/IntegrationTestBase.java
	hbase-it/src/test/java/org/apache/hadoop/hbase/chaos/factories/NoKillMonkeyFactory.java
HBASE-10314 Add Chaos Monkey that doesn't touch the master (Elliott Clark)

Conflicts:
	hbase-it/src/test/java/org/apache/hadoop/hbase/chaos/factories/MonkeyFactory.java
	hbase-it/src/test/java/org/apache/hadoop/hbase/chaos/factories/StressAssignmentManagerMonkeyFactory.java

Includes license addendum.

Amending-Author: Andrew Purtell <apurtell@apache.org>
Amend HBASE-12314 Add chaos monkey policy to execute two actions concurrently

Port changes in HBASE-12314 made in branch-1 and later with
HBASE-11348 in place

Amending-Author: Andrew Purtell <apurtell@apache.org>
HBASE-12322 Add Clean command to ITBLL

Conflicts:
	hbase-it/src/test/java/org/apache/hadoop/hbase/test/IntegrationTestBigLinkedList.java

Signed-off-by: stack <stack@apache.org>
Amending-Author: Andrew Purtell <apurtell@apache.org>
HBASE-12336 RegionServer failed to shutdown for NodeFailoverWorker thread (Liu Shaohui)
HBASE-12375 LoadIncrementalHFiles fails to load data in table when CF name starts with '_'

Signed-off-by: stack <stack@apache.org>
HBASE-12381 use the Maven Enforcer Plugin to check maven and java versions.

Signed-off-by: stack <stack@apache.org>

Conflicts:
	pom.xml
HBASE-12384 TestTags can hang on fast test hosts