Security fixes:

* Strip lookup calls out of inventory variables and clean unsafe data
  returned from lookup plugins (CVE-2014-4966)
* Make sure vars don't insert extra parameters into module args and prevent
  duplicate params from superseding previous params (CVE-2014-4967)
[mount] Add documentation for fstab option
[mount] make sure fstab exists

This is mainly to prevent from failing with no such file or directory
during module execution.
Fix ec2_setup task param quoting
Merge pull request #8223 from renard/create-fstab-if-not-exists

Create fstab if not exists
service: test properly whether systemd is running

Use a pure Python reimplementation of the [sd_booted(3)][1] function
from [systemd v210][2].

[1]: http://www.freedesktop.org/software/systemd/man/sd_booted.html
[2]: http://cgit.freedesktop.org/systemd/systemd-stable/tree/src/libsystemd/sd-daemon/sd-daemon.c?id=v210#n465