HBASE-12237 HBaseZeroCopyByteString#wrap() should not be called in hbase-client code
HBASE-12242 Fix new javadoc warnings in Admin, etc.
HBASE-12083 Deprecate new HBaseAdmin() in favor of Connection.getAdmin()

Conflicts:
	hbase-client/src/main/java/org/apache/hadoop/hbase/client/HBaseAdmin.java
HBASE-12029 Use Table and RegionLocator in HTable.getRegionLocations() (Solomon Duskis)

Conflicts:
	hbase-server/src/test/java/org/apache/hadoop/hbase/util/TestHBaseFsck.java
	hbase-server/src/test/java/org/apache/hadoop/hbase/util/TestRegionSizeCalculator.java
HBASE-12246 Compilation with hadoop-2.3.x and 2.2.x is broken -> HBASE-12220 Add hedgedReads and hedgedReadWins metrics -- REVERT
HBASE-10200 Better error message when HttpServer fails to start due to java.net.BindException(Kiran Kumar M R)
HBASE-12248 broken link in hbase shell help (André Kelpe)
Online config change

Summary: This diff is intended to forward port HBASE-8805 and HBASE-8544 implemented by Gaurav Menghani in 89-fb. This improves operational efficiency in managing clusters that are serving production traffic. The idea is to have a central configuration which can manage notifying the configuration observers. The observers in turn should update their local state from the latest config. Minor caveats where configuration variables are corelated should be taken care of with additional care.

Test Plan: Unit tests

Differential Revision: https://reviews.facebook.net/D24681

Signed-off-by: stack <stack@apache.org>
HBASE-12147 Porting Online Config Change from 89-fb -- JAVADOC FIX ADDENDUM