remove duplicate in cleanup list
change cleanup to set instead of list
Add python-posix-ipc dependency
add riemann client & facter dependency
Add posix lock on all iptables, ebtables and ipset commands.

This to prevent race condition when 2 or more instances of the script run simultaneously and could lead to a kernel EAGAIN message, which was ignored by the script
Revert "Add posix lock on all iptables, ebtables and ipset commands."

This reverts commit 53f0942e3d4a973a59729eb747c80af97479663f.
Add posix lock on all execute cmd.

This is required to prevent a race condition when 2 or more instances of the script running simultaneously could lead to a kernel EAGAIN message when managing iptables, ebtables, ipset rules. Such error is actually being ignored by the script
Integrate riemann alerting on deadlock
typo + add tag
Merge branch 'exoscalefix' into 4.3