Inject identities directory instead of using a controller.

Remove deprecated method that's no longer used.

Change-Id: Ia7e89f9d3de662451ccbec04eabf453478e256cf
Reviewed-on: http://gerrit.dmdirc.com/3017
Automatic-Compile: DMDirc Build Manager
Reviewed-by: Greg Holmes <greg@dmdirc.com>