Remove ParticleParameters

[nightm4re94]

What feature / which classes are you referring to?
ParticleParameter.

Describe what could be enhanced.
Instead of using ParticleParameters for Emitter configuration, we could slim down our API by using Attributes. Attributes are generic and offer more flexibility and in my opinion having two components with nearly identical functionality doesn't make sense.

Are there any alternatives to what you've considered? Please elaborate.
If we see a need to keep ParticleParameters specifically, we should document the difference properly.

Additional thoughts
Removing ParticleParameters would entail these changes:

• make Attributes serializable
• adjust Emitters to use Attributes instead of ParticleParameter
• Rename EmitterData to EmitterAttributes
• provide a detailed migration guide for existing projects since this is a breaking change.

[nightm4re94]

I got really lost here. Would appreciate if at somepoint someone could help me finish my branch.