Portals and others

+ End and nether portals with configurability
+ Bed homes
+ Cauldrons fill
+ Added time and weather saving
* ~~Fixes #1066~~
* Fixes #1012, fixes #1194

Portals don't construct/search for a destination portal yet.
Document the params, they seem a bit confusing - why give the world name AND the world? And what's with the respawn sending?