Create #markets infrastructure

[cbeams]

• Create Slack channel (#markets)
• Create GitHub repo by cloning and republishing dan-da/bisq_markets as bisq-network/markets per Transfer or fork markets app into bisq-network org github#20
• Set up notifications from GitHub repo => Slack channel
• Register repo in .mrconfig / .gitignore
• Link repo to bisq-network/dao ZenHub board
• Create bisq-network/roles issue as appropriate (Markets Website+API Operator/Maintainer roles#9)
• Update bisq-network/roles README as appropriate
• Create GitHub team as neccessary
• Grant GH team admin access to repo

[cbeams]

Closing as complete.