Cherry-pick 5985386
Add note about quickinstall script internet access requirement.
The quickinstall script downloads packages from the internet, so it
needs internet access to properly function. Also cleaned up trailing
whitespace.
(cherry picked from commit 598538690cede66bc5a75f995ba339d114cf84c4)

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

Updated links to point to new installation material. This page will improve significantly in 3.6.
Update whatsnew.markdown

Updated the link to install Enterprise (Vagrant environment) so that users will go to our new material.
Update installation-enterprise.markdown

Updated disk space requirements.
Update installation.markdown

Move Enterprise installation to top of list per Adi request.
Update installation-community.markdown

Change Sorting from 10 to 50 to move Installing Community to the bottom of the list (per Adi request).
Merge branch '3.5' of https://github.com/cfengine/documentation into 3.5