Epic #62041: twbs Bootstrap backend, refactor EXT:t3skin and HTML5 output
Refactor FlashMessages to TWBS alternatives
FlashMessages should be refactored to be compliant with TWBS alert boxes or Panels.
Right now FlashMessages are mis-used for different kinds of information.
A FlashMessage is a container for temporary information often closely bound to an action a user just did.
A Panel is an container that holds permanent information that needs emphasize this particular part of information as "important".
So an alert (FlashMessage) should always be dismissible.
This way we don't need to take care of making an alert optionally dismissible and create a strong default.
Another story are parts like the reports module.
Here FlashMessages were mis-used because up to now there was no other standard of highlighting a piece of information as success, notice, alert, danger.
The task is to check each use of FlashMessages (about 800 occurrences at the time of writing) and make sure whether this FlashMessage is really a FlashMessage or if it is some mis-used occurrence.
In order to make Alerts dismissible alert.js from TWBS needs to be loaded into the BE.