follow up to PR #1393

Backend should be always totally closed for indexing by search engine robots

we should not provide one in the package but developers should commit
them when starting a new project so that all share the same versions
and only explicit composer update command will change that.
Escpecially important when deploying to production.

This reverts commit a28e7470.

Cleaned up a few comments ... hope its not my OCD again... :-)

Reverted name to ```closeButton``` to be in sync with the bootstrap ```Alert``` widget.