Add information about RFP, tweak homepage layout

We've been getting emails related to API cloud recently. Instead of writing custom emails every time explaining how we are doing an RFP, API cloud might be replaced, and the developer portal is a proof of concept, I created a blog post explaining all this information to make future communication easier.

I also went ahead and restructured some of the content to remove placeholders, since we were getting questions about "Do I not have access to this documentation or is there just nothing there?"

My main goal here was to be transparent about how the developer portal is a proof of concept, and that we're in an RFP to potentially replace API Cloud.

@jont, @NUWAN.KUMARASIRI (and others are welcome) - could you take a look?

New homepage: