Introduce Tag Aliases and Tag Implications

Right now, users can tag their content with just about anything. Because of this, we have cases such as one person tagging their content "*Fullmetal Alchemist*" while another tags theirs "*FMA*." In this case, checking either tag, you won't see the other, despite that they are aliases of the same property. Similarly, someone might tag "*Fullmetal Alchemist: Brotherhood*," which would also be separate despite implying relation to "*Fullmetal Alchemist (Series)*." I recommend adopting tagging systems used with boorus such as Danbooru: [Tag Aliases](https://danbooru.donmai.us/wiki_pages/help%3Atag_aliases) and [Tag Implications](https://danbooru.donmai.us/wiki_pages/help%3Atag_implications). This allows tags to be associative and imply relations to each other non-destructively, making searching and tagging easier in the long run. I do understand this will require upkeep for maintaining aliases and implications, not to mention the actual implementation of the systems. That said, the current tagging system is not serving the site well, so in the long term I believe this would be worth the investment.