Suffix all subscribers with *Subscriber.
Use an event to generate the asset path.
Use the correct event name to organize stylesheets.
Display an html icon to indicate inline and standalone files in BE listing.
Display the assigned layouts in BE listing.
Inject the developer tools code after the base tag.
Fix environments isTablet() and isMobile() detection if overwrite is active.
fixup! Use an event to generate the asset path.
Use events to strip and add the static url.
Remove obsolete method ThemePlusUtils::storeAsset().
fixup! Use events to strip and add the static url.
Load related data container only in BE mode.
Fix endless recursion when generate assets path.
Use situation optimized async scripts.

The original async script was optimized to run with the debug tool and
multiple files. But when no debug tool is available (= production mode)
or only one file is used, the async script was realy heavyweighted.
Now there are multiple implementations for single and multi file usage
and for production and development usage, that are optimized for the
specific situations. This make the async script more lightweight.
Reformat code and organize imports.