[cmaster-next] Slack - upgrade to standard edition?

Donald, (and everyone else working on it) Thanks for setting up Slack. We (NetDEF) can get a free upgrade to the standard edition as part of bing a 501c3 non-profit. See https://freerangerouting.slack.com/pricing for difference between Free and Standard model. Happy to do this if this community thinks Slack is useful. Please be aware that it’s free “only” up to 250 users - and 85% discount above it. We can only do this for one Slack - so we may want to wait until everyone confirms the new selected name (i.e. no legal issues) - Martin