Board Decisions/20191219-002-Use public communication

Matter
https://mail.jabber.org/pipermail/members/2019-December/009055.html

re-affirm Board uses public communications channels (such as members at xmpp.org, xsf at muc.xmpp.org) as much as possible, and board at xmpp.org is strictly for matters that are (initially) confidential.