Improve the affiliation scheme of the OSMF

Currently, the OSMF only recognizes geography-based Local Chapters as affiliates of the Foundation (see the Local Chapters page on the OSMF website). The Foundation has now recognized over 10 Local Chapters.

It was observed that having Local Chapters as our only affiliation model is too limiting and sometimes provides a high or unreachable burden for various OSM communities worldwide. For instance, having a Local Chapter in Cuba is all but impossible. So, taking a leaf from other open-data and open-knowledge communities such as the Wikimedia Movement, it was recognized that other forms of affiliation model would be nice to have. One suggested model is to have a lightweight user group model that can be used in lieu of or as a stepping stone to Local Chapter status. Another model is to also recognize thematic groups or communities such as the Humanitarian OpenStreetMap Team and GeoChicas.