Alias spike -> spikes

BUR #12672 has been approved by @nonamethanks.

create alias spike -> spikes

Ambiguous/redundant tag. Currently it's used mainly for posts with a single spikes, but it's also been used in the past for the volleyball move, characters name 'spike', and horns.

Deprecation is better than an alias because the tag is ambiguous and spikes comes up third in search when "spike" is entered (so deprecation probably won't impact find-ability).

Edit: Eh, whatever, an alias works just as well (BUR used to be deprecate spike)

Edit2: I removed all the posts that obviously shouldn't be tagged spikes, so the BUR is good to go on that front.

Edit3: Title update

I think an alias to 'spikes' is a better solution. Has a larger pool of submissions. I doubt one's pickiness vs plurality is much of a concern for most people who aren't likely to even be using these tags in a singular fashion by themselves anyway.

The bulk update request #12672 (forum #223521) has been approved by @nonamethanks.