create alias snow_miku -> yuki_miku
The term Snow Miku has been used widely even in the official site http://snowmiku.com/
Even looking up in google, "snow miku" shows far more results than "yuki miku" or "雪ミク"
Also, while on the topic, why are there no separate tags for the yuki_miku of each year? The designs each year are very different so I thought it'd be better if they are separated. Like yuki_miku_ichigo_shiromuku or yuki_miku_2013 for post #2897725, yuki_miku_twinkle_snow or yuki_miku_2017 for post #2567430 and so on.
EDIT: The tag alias snow_miku -> yuki_miku has been approved by @NWF_Renim.
Updated by DanbooruBot