Add missing quotes.
Update documentation.
Vagrant: Install icinga-web.
Vagrant: Restart Apache after installing icinga-web.
Revert "Vagrant: Restart Apache after installing icinga-web."

This reverts commit 7965713617cb38d36e6b0cc5e4579c8b482d3e5a.
Vagrant: Restart Apache after installing icinga-gui and icinga-web.