v1.1.0-rc1

MI-814: Render a template for atlassian-connect.json file. (#19)

* Use a template for atlassian-connect.json file.

* Fix formatting

* Fix plugin url path

* Code refactoring

* Add a slash command to show URL for atlassian-connect.json file.

* Update the list of available commands

* Add help commands.

* Use constants

* Fix lint

* Fix failing test
- Update .gitignore