Add links to CFEngine 3.5, Getting Started, and Tutorials pages (new-users.html page)
Merge pull request #202 from deb-cfengine/primer_links

Add links to CFEngine 3.5, Getting Started, and Tutorials pages
Fixing documentation for call collect

The documentation mentioned "collect call", however the server
is sending "collect_calls". Fixed the documentation so it matches
reality.

PS This was correct in the older documentation, somehow it got
changed.

(cherry picked from commit 04e9217e2e3f9c47d7a62821a34b93206c90dde6)
Add documentation for process table cache in state dir

(cherry picked from commit 04393a424c0dd0c21f56e978eebd8e7495b3c686)
Add links to community package locations
Fix hyperlinks
Add link to enterprise download area
Ref #3678: Add missing sys.last_policy_update

(cherry picked from commit 75d415b08e0ba30bf63b206ef08215225cea83ba)

Conflicts:
	reference/special-variables/sys.markdown
merge all installation docs to 3.5
Minor tweaks to all docs; added Feedback page to installation docs
(cherry picked from commit dd8938b946d42d4765e042a5ed36baa4186af17f)

Conflicts:
	getting-started/installation.markdown
	getting-started/installation/installation-community.markdown
	getting-started/installation/installation-enterprise-free.markdown
	getting-started/installation/installation-enterprise-vagrant.markdown