Revert "Nx does not need to ssh around anymore"

This reverts commit f8485527d05cf6510b2231dbe161d076c97d4f84.
Revert "Xylo module should not be storing private keys"

This reverts commit c23e04d6d5784f677936dca6a8ebc6f04394a233.
Enable postfix so cron emails

Signed-off-by: Konrad Scherer <Konrad.Scherer@windriver.com>
Install mosh on all Redhat systems
Raise process limit on all machines setup to build wrlinux
Add leads to sudo access on yow-git
Increase nx timeout to two hours
Add leads to sudoers for all yow and ala machines
First attempt to send nx build stats to graphite
Add some output to graphite script
Fixed up nx stat aggregation
Increase snapshot size. Failures seem to happen at 50% snapshot size
Install screen and gdb on all machines doing builds
Add xylo to sudoers without password on ala-blade1
Add storage spec for nx stats
Dell omreport has moved to new package with OpenManage 7.2
Add screen to required host packages
Convert build time to decimal hours
Fix conversion of time less than one hour
Update host package install script to output text if all packages are installed

Signed-off-by: Konrad Scherer <Konrad.Scherer@windriver.com>