Added support for Erfurt cache.
Integrated new Erfurt cache in extension scan process.
Merge branch 'feature/cache' of github.com:AKSW/OntoWiki into feature/cache
Use central Erfurt cache within translation resource instead of own file cache.
Use central cache in extension manager and remove deprecated code lines.
Update clearing of extension cache according to central cache.
Use central cache in general view class instead of own module cache.
Merge branch 'develop' into feature/cache
switch to Erfurt feature/cache
Extend cache configuration defaults.
Extend and document cache configuration.
Show information about cache frontend and backend in about controller.
Extend about information by temp dir, provided by new Erfurt_App method getTempDir.
Remove cache folder checks which have been moved to Erfurt application.
Show current temporary directory in about controller, use Zend method.
fix test target for file cache backend, ignore cache dir
Merge branch 'feature/cache' into develop

Conflicts:
	libraries/Erfurt