Re-organise/restructure configuration schema/file

[zoton2]

We have already made a few tweaks to the configuration schema/file in v2.x but some bigger changes that can't be done (or maybe can be but are way too complicated to support both old and new) should be made so there's less repetition. Here's the ideas right now:

• Move horaro and oengus into schedule.
• Move some duplicated/shared properties from inside horaro and oengus into schedule.
• Remove all deprecated parts.