We keep the parent change separate for two reasons. It serves as a
record that we did step through 3.6 on our path to 3.7 and this allows
us to test 3.7 without impacting the 3.6 upgrade if our testing shows
problems with 3.7. Note, we'll keep the zk04-zk06 servers in the
emergency file until we're satisfied with an end result just to avoid
any unexpected (down|up)grades.
Change-Id: Ief008808d1296ae673059f1c40961a63a86f768d
2a8124fbbe