Add systemd service files
tests/acceptance/README: Add git bisect notes from @cdituri in #1317
Allow JsonParse to parse primitives at top level

Also, add JsonPrimitiveTypeToString
examples/container_iteration.cf: add useful example
Merge pull request #1632 from nickanderson/contrib/systemd

Add systemd service files
tests/acceptance/bisect-acceptance.pl: automagic git bisect script.

- automagically git bisect against a supplied CFEngine acceptance test
- hunt down the commit that either introduced a regression or fixed a bug
- respects bzr's notion of yes|no -vs- git's notion of good|bad; less
  confusing when hunting down the change that _fixed_ a bug.
examples/getvalues.cf: show data container too
Spelling correction: Commerical -> Commercial
Merge pull request #1651 from bahamat/master

Spelling correction: Commerical -> Commercial
Merge pull request #1648 from jimis/minor

Valgrind friendly openssl, if getenv("CFENGINE_TEST_PURIFY_OPENSSL")
Fix package_list_update_ifelapsed having no effect on "apt-get update"

Redmine #3981, #5339.

It is documented as having the described effect, but does not.

The timestamp for the last update is now maintained by a timestamp
file, /var/cfengine/state/software_update_timestamp_<manager>, where
<manager> is the package executable that is being used for the current
promise.
Ideally it should be integrated with the database, but we want the low
risk solution right now, and we plan to replace this code anyway.
Print errno related string when SSL_read/write fail with SSL_ERROR_SYSCALL. Also moved a docstring to the proper place.
Changed wording to something nicer.
docstring fix.
SO_REUSEADDR missing is not a reason to WARN loudly. Demote to VERBOSE.
Demoted to VERBOSE the instructions on how to trust a new client.
Fix wording when trust fails, so that messages are not so aggressive.