[INTERNAL] add file system implementation for IntelliJ

Change-Id: I6fe569eeef70c08c25e7b8366805d0ae81693362
Reviewed-on: http://saros-build.imp.fu-berlin.de/gerrit/1644
Tested-by: Jenkins CI
Reviewed-by: Arsenij Solovjev <xeper000@gmail.com>
Reviewed-by: Franz Zieris <zieris@inf.fu-berlin.de>