[bisq-contrib] New #growth infrastructure

[Chris Beams]

As you may have noticed, we’ve put several new resources in place to help foster Bisq’s growth:

 - The #growthhacking channel in Slack, where we’re discussing and brainstorming
 - The https://github.com/bisq-network/growth repository, where we’re capturing concrete ideas and experiments
 - The upcoming (possibly weekly) growth Zoom calls, where we’ll discuss the experiments we’ve been working on and plan which experiments to work on next.

Please join / subscribe to any and all of these as you see fit, thanks!