Improvements with 2.3.0

• New Feature: Now supports Aseprite files for animated tiles.
• New Feature: New Tileset Atlas asset type added. This allows us to easily add all sprites in a TSX tileset to a Unity Sprite Atlas, eliminating any visual seams between tiles
• Bug fix: Super Tiled2Unity no longer tries to automatically chop up source textures into sprites. This was leading to too many issues.