Add buildout configurations for Plone 5.0
Revert "Use Plone 4.3.2 until release of universal installer"

Universal installer for Plone 4.3.3 has been released: https://launchpad.net/plone/4.3/4.3.3

This reverts commit 8aabcfad173e8e4358745af1decefd3f6726316d.