Revisit dev guide why review/why open

[stefaniebutland]

I felt like we needed a "why review" section. Something about uniqueness of the system. And benefits to participation. Was at a loss so I copied txt from dev guide

Noam suggested deleting this so we did ("This seems out of place? It's a useful piece of info but I'm not sure why it's the one that is pulled out of the guide and put first. I was going to move it down, but I actually now think it should be removed; it doesn't follow the flow of the section.")

Why are reviews open? Our reviewing threads are public. Authors, reviewers, and editors all know each other’s identities. The broader community can view or even participate in the conversation as it happens. This provides an incentive to be thorough and provide non-adversarial, constructive reviews. Both authors and reviewers report that they enjoy and learn more from this open and direct exchange. It also has the benefit of building a community. Participants have the opportunity to meaningfully network with new peers, and new collaborations have emerged via ideas spawned during the review process.