Better advertising (e.g. releases/news/blog)

[rahulsavani]

In time for Gambit 17 we want to improve several aspect of our externally-facing comms, including for example:

1. A clear place on the website that shows the current release, like the following from the pandas site:

   

2. Possibly turning on the blog feature of our website, where we can advertise things like the upcoming JOSS paper;

3. Some way to enlist alpha/beta testers.