upd: lavel-schema, added coast and coastIndent.
mod: reverted coast textures back to smaller ones.
fix: level's coast direction is not mirrored anymore.
ren: level coastIndent -> coastDistance.
mod: unified spot type "island", no "atoll" anymore.
mrg: unified-island-type.
mrg: bug-fixes and new features.
mod: converted level data from coastIndent to coastDistance.