[HDFS-447] Restoring the HDFS preInstallNotes to the exact wording as in Universe (#825)
[HDFS-447] Restoring the HDFS preInstallNotes to the exact wording as in Universe (#825)

* Restoring the HDFS preInstallNotes to the exact wording and ordering as currently appears in Universe.

* Moved all "preview" statements to beginning.

* Finalized text from Suzanne for hdfs package install.

vishnu2kmohan/dcos-commons,mesosphere/dcos-commons,mesosphere/dcos-commons,vishnu2kmohan/dcos-commons,vishnu2kmohan/dcos-commons,mesosphere/dcos-commons,mesosphere/dcos-commons,vishnu2kmohan/dcos-commons,mesosphere/dcos-commons,vishnu2kmohan/dcos-commons