Clarify differences between 'Free' and 'Bronze' GitLab.com plans

On https://about.gitlab.com/gitlab-com, we advertise that 'Free' accounts get Community Edition features, while 'Bronze' gets Enterprise Edition Starter plus support. In reality, GitLab.com is running EE and there is no difference between 'Free' and 'Bronze' with regard to features they get on GitLab.com. The only difference currently is they get support.

We should update the page to make this a bit more clear. We had at least one customer that bought Bronze and then asked support "Where are my extra Enterprise features?"