Make a clear pathway to become a Foundation member

[Maryblessing]

Work with Katie on this as she's leading it.

[Maryblessing]

Katie and I agreed to set up a recurring meeting where we discuss this and map out plans to move things forward. We'll meet every other Thursday until we've made significant progress on this.

I also made an attempt to define this in the Contributor Ladder doc I worked on. See this issue #444