WINPKG CHANGES: Everything from baikal to champlain

We are bringing in as one commit. This is a squashed commit of the following
commits. This will skew the author information, but for the real author
information, please use the commits that are showing in as cherry-picks
from the original commit's

BUG-12086 MSI Packaging Changes for Tez (cherry picked from commit 7cfafcc9ff8914af0ce414246ea8739c6dc2bc31)

14703-TEZ-site-xml-has-wrong-syntax
(cherry picked from commit c5d9087631df55035ae6763c7cb6c89a1d06a71a)

BUG-14691 MSI installer should update tez.lib.uris in tez-site.xml
(cherry picked from commit 1496720a4b521a366bb39c680bfd71bc4ca12ff3)

BUG-14606 setting TEZ_CLASSPATH, so that the downstream components can
use it to append to their classpaths
(cherry picked from commit a417f87b8865e0c66efbcf0a79fdd169f31feab9)

BUG-14606 setting TEZ_CLASSPATH, so that the downstream components can use it to append to their classpaths
(cherry picked from commit 08a7313f6e7da222d87e7a0858feb9b18d07067a)

Set the TEZ_CLASSPATH only if TEZ is enabled
(cherry picked from commit f228efe97b75e526471a24cdb3bd9d68d05baac8)

BUG-15958 BUG-15932 fixup errors in yarn RM HA configs
(cherry picked from commit da8ca42318254acb498e5a62dd60a055e87ca8f0)

BUG-16120  BUG-15958 BUG-15932 Windows RM HA  config changes
(cherry picked from commit e069d7f67bfb5b33187d8e0a906bfc8d6a910307)

BUG-16254 tez-site.xml has wrong configs for hdfs in HA mode
(cherry picked from commit 234df859a946a622656c0b195e9b8768a85b70ed)

BUG-16245 Missing optimization configs on Windows
(cherry picked from commit 2d12c62a406efa39f765e6fe5b46bb0e5f3e3898)

BUG-16631. Increasing client timeout in tez-site.xml
(cherry picked from commit b33677a70cd1cbbf53b85fa045f1083a294c9e1a)