Add a Big Bang Blog folder + 2.0 Blog Post

General MR

Summary

This MR adds a blog folder that can be leveraged in the docs compiler to add a blog link to our docs site.

Also included is a single blog post - focused on the what and the why for BB 2.0.

Preview of the 2.0 Blog post: https://repo1.dso.mil/big-bang/bigbang/-/blob/blog-2.0/blog/01-big-bang-2-0.md