Revert "Re: #541 - Utilize IComponent::AttributesChanged for EC_ParticleSystem

fixes #607

---rest of the reverted commit message:

...and EC_Billboard components. EC_Fog left untouched intentionally as it wouldn't gain anything from the refactoring (it's not interested in which attributes have been changed, as it does the same update routine always)."

This reverts commit 0fba536ad4316235fc2ae601bf86fab004