Dumping league metaclasses

Used for code-gen of .bin (de)serialization classes: https://github.com/LoL-Fantome/LeagueToolkit/tree/master/LeagueToolkit.Meta.Classes

Usage:

# Clone the repo
git clone https://github.com/LoL-Fantome/LeagueMetaJson

# The script expects to be in same directory(PR welcome)
cd LeagueMetaJson

# Dump any new version detected
python3 dump_manifest.py