SBON <-> YAML conversion utility

Helps to identify planet files:
```bash
./yamlconv.py --src gamma_-74079817_61498032_9165529_11_11.world --load \
  --dive '/meta/0/worldTemplate/celestialParameters' \
  --filter ,coordinate,scanData,name --dump
```
```yaml
coordinate:
  location: [-74079816, 61498032, 9165529]
  planet: 11
  satellite: 11
  sector: gamma
name: Gamma Ultragon Minoris III d
scanData:
  # [...]
  threatLevel: 3.0
  undergroundLevel: 1150.0
  worldSize: [6016, 4000]
```
Unfortunately, conversion is one-sided as of date.