This updates Review Board to work with the new support infrastructure

being deployed on our servers.
rb-site now asks for a Company name, which can also be provided later on

the General Settings page. This name will show up on the support page

when users visit it. We may also want to use this down the road to help

brand Review Board itself.
rb-site will also ask for permission to collect support data, and

explain what we collect and how it's used. This can be changed later

through a checkbox on the Support Settings page. If allowed, rb-site

will up and maintain the support page on install and upgrade.

Set the company name on an existing server and saw that it saved.
Toggled the new checkbox for support data and saw that data was only set

when it was checked.
Created a new site and entered a company name. Saw it was saved and showed up

in the support page.
Tested various input for the permission check in install, and tested that they

had the expected outcome. Also tested this with the new --opt-out-support-data

option.