(#21198) Allow data bindings w/ hiera to get special vars

Hiera functions get several extra variables that are often used during
classification. The hiera data bindings didn't provide these same
variables and so transitioning from functions to data bindings was
impossible at times. This changes data bindings to pass the whole scope
through (the only way to produce the calling_class and module) and then
wraps it in the Hiera::Scope object to make the variables available.

This replaces an acceptance test with an integration test that checks
the same functionality, but without needing to run an entire machine to
check it.
(Maint) Translate acceptance test to integration

We can make the same check much faster by converting this check to an
integration test.
fixed sendmail

Sendmail usage lacked a blank line after "To:" field. Which sometimes caused blank emails being sent.
(Maint) Remove unused example manifests

These manifests seem to have been created when some various issues were
fixed and functionality was added. However, they are not a comprehensive
(nor updated) example of how to use puppet. Keeping them here probably
ends up being a distraction for those who find them.
(Maint) Update commands to use new forms in hiera examples

The hiera examples were written assuming that puppet apply was just
puppet (the old form), and that hiera was not always available (and so
set the libdir).
(#7911) Fixed exception when using forcelocal param

When the user resources had forcelocal set to true the provider would throw the error "undefined method `intern'".  This was because the gid method was being passed to a should call rather than a symbol.  Arguments passed to should need to be symbols.
(#22458) Always store the path for launchd service provider

Otherwise the path won't be found next time the provider is asked for it
Merge branch 'pull-1883'

This closes GH-1883
Merge pull request #1917 from mihau/patch-1

Add missing newline in sendmail usage to tagmail
(doc) Mark some of the Provider API public
Merge pull request #1913 from zaphod42/issue/master/21198-missing-vars-in-data-bindings

(#21198) Allow data bindings w/ hiera to get special vars
Merge pull request #1927 from jjulien/iss7911

(#7911) Fixed exception when using forcelocal param
Merge pull request #1937 from zaphod42/maint/master/cleanup-examples-dir

(Maint) Documentation fixes
Merge remote-tracking branch 'upstream/master' into fix/master/shell_validation
unnecessary extra lines