Make it clearer that permission to use includes gen 8 sprites

Currently, the information is written as such: While it is simple to reasonably conclude this included gen 8 'mon, due to children being allowed to use this site I think this line being as specific as possible will help users who may not understand that the gen 8 sprites were also made by the PFQ art-team. Additionally, I have met adults in my life who do not understand permission to use for art, so it may help teen and adult members as well who may not know about art permissions. Pros: Clearer rules, less confusion, may help prevent kids from getting confused and accidentally breaking the rules Cons: Would need to be edited again when future spoiler 'mons are added (gen 9, any forme changes similar to mega, etc)

I've just adjusted the thread to make it more clear :)