Core pr 4

Added new date formats and basic OG and OG menu settings (mainly used by ding_library and ding_groups).
Added new theme functions to style lists across other ding modules.
Fixed a lot of different bugs.
I do not follow. Other modules contain default configuration that should not change e.g [`ding_news`](https://github.com/ding2/ding_news/blob/master/ding_news.info). `ding_varnish` could easily become a feature module.