Adds unit test for new apps:rename function.
Add example in the docs for new apps:rename function.
Add apps:rename command to help command.
Delete cache directory before copying old app directory to new app directory.
deploy_app instead of create_app for apps:rename testing.
Change app url to match new name. Fix unit tests.
Add some more tests, plugn triggers.
- Specify how long to wait before running first check
- Specify timeout for each check
- Check specific hosts, e.g. http://signin.example.com
- Check both HTTP and HTTPS resources
