enforce no enteractiveness installing pkg with apt

use the same env vars and dpkg options as for the upgrade function
also link check mode to --simulate option when installing a pkg

fixes #2763
Merge pull request #2771 from sergevanginderachter/apt-noninteractive-install

enforce no enteractiveness installing pkg with apt
Corrected instance password data check.  Previously broken after adding region support.
Merge pull request #2772 from lwade/ec2_volattr

Corrected instance password data check.  Previously broken after adding ...
Catch exception when logging to systemd journal fails

systemd journal will throw IOError exception when journal.sendv() fails.
This catches that and falls back to syslog.  See issue #2773.
Merge pull request #2774 from sfromm/issue2773

Catch exception when logging to systemd journal fails
Changes to allow WANT_JSON to allow JSON to non-Python modules
Improve variable smushing so it only has to be done in one place.   This is related to shlex.split being called
on untemplated variables in some rare cases.
Flush handlers before pre and post task sections change, but not between task and roles, as this seems
to be confusing to people (and not usually neccessary)
Update role example to show tag usage
Merge branch 'devel' into local