HBASE-13229 Specify bash for local-regionservers.sh and local-master-backup.sh

Signed-off-by: Sean Busbey <busbey@apache.org>

bin/local-master-backup.sh

@@ -1,4 +1,4 @@
-#!/bin/sh
+#!/usr/bin/env bash
 #/**
 # * Copyright 2007 The Apache Software Foundation
 # *

bin/local-regionservers.sh

@@ -1,4 +1,4 @@
-#!/bin/sh
+#!/usr/bin/env bash
 #/**
 # * Copyright 2007 The Apache Software Foundation
 # *

src/main/asciidoc/_chapters/configuration.adoc

@@ -172,6 +172,9 @@ session required  pam_limits.so
 ----
 ====
 
+Linux Shell::
+  All of the shell scripts that come with HBase rely on the link:http://www.gnu.org/software/bash[GNU Bash] shell.
+
 Windows::
   Prior to HBase 0.96, testing for running HBase on Microsoft Windows was limited.
   Running a on Windows nodes is not recommended for production systems.