Change world time start from dawn to midnight
Merge PR #1336 by @msteiger - time tweaks
Use the inheritence cache in all getElementStyle methods.

Reduces unnecessary object allocation.
Update readme - new modules and credits update
Separate celestial events into new package
Climbing improvements
Extract celestial model into it's own class
Merge PR #1340 by @meniku - climbing improvements
Readd the old ladder (dug out of the legacy branch)
Merge PR #1337 by @flo - ui cleanup
Merge PR #1338 by @msteiger - refactor celestial / time setup