Antialiased Line2D - Better antialiasing for 2D line/polygon/circle drawing

This add-on provides higher-quality, more portable antialiased Line2D drawing compared to the default Godot implementation.

Features:
- Supports opaque and translucent Line2Ds with any joint and cap type (including multiple overlapping Line2Ds).
- Supports lines of any width (constant or variable over a curve).
    - Lines with a thickness greater than 256 pixels may appear slightly blurry, but will still render correctly.
- Features an AntialiasedPolygon2D helper node to draw 2D antialiased polygons, keeping the polygon and line in sync.
- Features an AntialiasedRegularPolygon2D helper node to draw 2D antialiased circles and other regular polygons (such as hexagons).
- Supports Camera2D zoom and multiple resolutions.
- Works with both the GLES3 and GLES2 renderers.
- Works on desktop platforms, Android, iOS and HTML5.
- High performance, as only a single 256×256 custom texture is used.
- Can convert existing Line2D nodes to use AntialiasedLine2D (see the usage documentation). This way, you don't need to redraw lines you've already drawn.

See the usage documentation at: https://github.com/godot-extended-libraries/godot-antialiased-line2d

Demo project: https://godotengine.org/asset-library/asset/1267

4.x version of this add-on: https://godotengine.org/asset-library/asset/3103