Disable dashboard for already on-boarded projects (fixes #8).

Because repository configurations always take precedence over the global configuration, if the global config says the dashboard is disabled, but the repository config enables it (via config:base) then the dashboard will be enabled.

Existing on-boarded projects were on-boarded with the config:base preset, which includes the dashboard.

Although the global on-boarding config is set now to disable the dashboard (see

I believe this ignorePresets option will disable it even for those.