Update upgrade instructions for 0.7.0

This patch also changes the way we track upgrade instructions. From now
on we'll only give the instructions from going to the previous latest
to the newest. This makes sense since we don't test upgrading from
other versions, nor do we want to.

Change-Id: I8be0ef7ca5f32f1f91504866dfe34a6be0550705
Reviewed-on: http://gerrit.cloudera.org:8080/2353
Reviewed-by: Misty Stanley-Jones <misty@apache.org>
Tested-by: Kudu Jenkins
Reviewed-by: Todd Lipcon <todd@apache.org>
(cherry picked from commit 8eec83f9579e80afa8e8b2c6293433ce68e77d39)
Reviewed-on: http://gerrit.cloudera.org:8080/2521
Reviewed-by: Mike Percy <mpercy@apache.org>
Tested-by: Jean-Daniel Cryans
2 files changed