Inject the config directory.

Introduce a new dagger module that exposes the results of the
command line parser, such as the config directory.

This will let us inject the relevant directories into managers
and simplify the creation logic.

Change-Id: I9548f6ab11d76e03f25c0cd2a164032073b9ffd1
Reviewed-on: http://gerrit.dmdirc.com/2686
Automatic-Compile: DMDirc Build Manager
Reviewed-by: Shane Mc Cormack <shane@dmdirc.com>