Alias 'pinkitty pie' to 'pinkie cat'

pinkitty pie → pinkie cat
 
I don’t know how we came to have two tags for Pinkie Pie dressing as, species swapped to, or behaving in the manner of a cat, let alone why one tag implies the other. A quick search of the forums turned up nothing why that might be and the two tags look to be identical in use.

Done.