OSGi Installer: Persist (optional) error text per resource

[Konrad Windszus]

Currently the OSGi installer web console will just expose a state like 
„Ignored“ or „Install“ in case a bundle/config/package could not be installed. 
It would be very helpful (especially in the context of SLING-5014) to 
additionally persist some error text on the last action, if it was not 
successful. This error text should be exposed through the web console. That way 
one could easily determine (even afterwards) why a specific artifact was not 
installed by the installer.
WDYT?
Konrad