fix: doc/examples/particles, added web to .gitignore
feat: doc/examples/particles, added more examples,
refactor: Particle does not extend Component
refactor: Particle subclasses in separate folder
refactor: ParticleComponent is now simple container
fix: SingleChildParticle, asserts for child existing
feat: AnimationParticle for Flame Animation
feat: ComponentParticle for Flame Component
feat: SpriteParticle for Flame Sprite
