Release Notes for 1.0.0

This is a significant breaking change from pre-1.0 releases. Especially:

changed the user from app (uid=1001(app) gid=1001(app) groups=1001(app)) to node (uid=1000(node) gid=1000(node) groups=1000(node),1000(node))
no longer installing bash, configure-wiki, nor set-owner-name
no longer creating /home/app/.wiki/wiki.json

Those changes in particular will impose some work on authors upgrading from previous versions.