Review request: HADOOP-11393

[Allen Wittenauer <aw...@apache.org>]

This effectively makes the bash code the same as the Windows code with regards to using HADOOP_HOME as the base of operation. It is a large patch, but all it does is:

	* replace every occurrence of HADOOP_PREFIX with HADOOP_HOME with the standard bits to use and give a deprecation warning if HADOOP_PREFIX is defined
	* replace DEFAULT_HADOOP_PREFIX in the trace utilities with DEFAULT_HADOOP_TRACE_PREFIX (which is marked as a private interface) so there is no confusion as what that is actually supposed to be

	I’ve re-submitted to Jenkins this morning, but it likely won’t return any viable results since it goes over the time limit.  (Although the weekend is normally super quiet so maybe it’ll run in record time or something?)

Thanks.