Merge the currently THREE separate Getting Started documents

Why do we have 3 separate Getting Started documents? How about merging them into 1?

1. https://www.opendaylight.org/installing-opendaylight (where is the source for that and how does one contribute to it?)

2. https://docs.google.com/document/d/12O86Nc4IbHvBC_ZGE_tHl0IWYd75Lk2HzfcV4YxhWTg/pub

3. https://github.com/opendaylight/docs/blob/master/manuals/getting-started-guide/src/main/asciidoc/bk-getting-started-guide.adoc (I'm assuming there is the HTML site of that? watch DOCS-16...)