1.13.0 (#675)

## Major features
- New API methods to: Add ship logs from xml, add dialogue from xml,
create a new planet from json string. All of these methods work directly
with strings or XElements and don't load files on their own.

## Improvements
- Pitch anglerfish sounds based on scale. Resolves #160.

## Bug fixes
- Fixes ship being broken when spawning on the center of the universe.
Resolves #648
- Fix Stranger cloak breaking on second loop onwards. Resolves #673.