DDBNEXT-75: Each controller should have an error handling (handled,
logged, error page displayed)
DDBNEXT-76: Removed datasource configuration
DDBNEXT-76: Added comments
DDBNEXT-75: Fixed syntax of error logs
Merge branch 'develop' of
https://github.com/Deutsche-Digitale-Bibliothek/ddb-next.git into
DDBNEXT-75

Conflicts:
	grails-app/controllers/de/ddb/next/ErrorController.groovy
DDBNEXT-75: Fixed some problems after the new code from DDBNEXT-74 came
in
DDBNEXT-75: removed testing code that cause a wanted crashing
DDBNEXT-75: Replaced direct 404 forward by a custom exception handler
Merge branch 'DDBNEXT-75' into develop

Conflicts:
	grails-app/controllers/de/ddb/next/AdvancedsearchController.groovy
	grails-app/controllers/de/ddb/next/SearchController.groovy
Merge branch 'DDBNEXT-76' into develop