Improve OSM feature generation capabilities

[SmylerMC]

Goal:

This PR aims to improve the way OSM features are generated into the world. It focuses on implementing new flexible internal mechanics so that users can configure OSM generation to suite their needs through the osm.json5 config. Actually implementing the new generation improvements in osm.json5 will happen in a separate PR as it will probably be subject to debates over personal preferences on how things look in-game.

Progress

• [x] Internal support for setting surface blocks at any height
• [ ] Internal support for setting surface blocks depending on the position and on a Random
• [x] osm.json5 support for multiblock patterns
• [ ] osm.json5 support for randomized patterns
• [ ] Doted SharpLines
• [ ] Internal support to generate small structures at the location of Points
• [ ] osm.json5 support for structures

Implementation

I'm trying to build on top of the current implementation to keep things as fast as they are, but a few changes have to be made to support the new features:

[DaMatrix]

this may be better suited to do on 2.0, as i've rewritten (and will be doing further major changes to) a lot of the OSM parsing code.

[SmylerMC]

this may be better suited to do on 2.0, as i've rewritten (and will be doing further major changes to) a lot of the OSM parsing code.

Ok, I'll be starting fresh from a new branch to avoid annoying conflicts then, do you think you could merge back master into dev/2.0 so it is up to date ?