message: Fix hyperlink for Hyperledger's Rocket.Chat
  The link for Rocket.Chat wasn't rendering correctly when viewed on
  GitHub.
diff: @@ -7,7 +7,7 @@ library; there are also convenience wrappers for various programming languages.
  All bugs, stories, and backlog for this project are managed through [Hyperledger's Jira](https://jira.hyperledger.org)
  in project IS (note that regular Indy tickets are in the INDY project instead...). Also, join
  -us on [Jira's Rocket.Chat](chat.hyperledger.org) at #indy-sdk to discuss.
  +us on [Hyperledger's Rocket.Chat](https://chat.hyperledger.org/) at #indy-sdk to discuss.
  ## Building Indy SDK
  