Use _ prefix instead of _real suffix on variables

On the whole, the style in manifests for variables that have been
modified in a local scope and saved to a new variable name have shifted
from using `$foo` -> `$foo_real` to using `$foo` -> `$_foo` due to the
shortness of the form and semantic implications that `$_*` is not
neccessarily human-friendly.
Update title/header to say JIRA rather than Redmine

Yeah, missed it first go-round.
Merge pull request #254 from laurenrother/JIRA

Update title/header to say JIRA rather than Redmine
Move "smart parameter defaults" into classes reference

This part from the old guide to parameterized classes is still relevant
and useful, so I’m moving it into the reference page for classes.
Removed references to the old guide

Replaced with links to the classes reference
(maint) Update community nav to point to jira workflow

The redmine workflow is gone, point to jira instead.
Merge pull request #255 from joshcooper/jira-nav

(maint) Update community nav to point to jira workflow
Merge pull request #256 from puppetlabs/remove-parameterized-classes-guide

Removed parameterized classes guide
Deleted parameterized classes guide.
Update instructions for installing a module from a release tarball

Remove link to bug, since it has been resolved, and update instructions
for installing a module from a release tarball and disabling the PMT
from attempting to resolve dependencies.
Merge pull request #257 from laurenrother/PR_reference_updates

Update instructions for installing a module from a release tarball
Docs updates for 3.4.0 final

Just moving the references, since they're unchanged, and adding a note about PUP-1015.
Moved PE user guide link on docs home page so it's easier to find.
Copyedit a stray sentence in modules_installing
Changes for 2.84 and 3.11
Copy edits to 3.1.1 appendix and what's new.
( DOC-9 ) Fix ordering of units for report prune rake task

This patch changes the ordering of the units for the report pruning rake task from random to descending chronologically. This makes the docs easier to read and understand.
Merge pull request #258 from llowder/fix_for_doc_9

( DOC-9 ) Fix ordering of units for report prune rake task
Copy edited
Merge branch 'master' of github.com:puppetlabs/puppet-docs