How do you rename an existing #slack channel name? https://get.slack.help/hc/en-us/articles/201654073-Rename-a-channel
How do you rename an active channel on slack? https://get.slack.help/hc/en-us/articles/201654073-Rename-a-channel
How do you remove a member from a private slack channel? https://get.slack.help/hc/en-us/articles/201898668-Remove-someone-from-a-channel
