Support for setting custom stopwords on Index Creation

[SimonJTurner]

From the Docs:

STOPWORDS {count}
sets the index with a custom stopword list, to be ignored during indexing and search time. {count} > is the number of stopwords, followed by a list of stopword arguments exactly the length of {count}.
If not set, FT.CREATE takes the default list of stopwords. If {count} is set to 0, the index does > not have stopwords.

Can be added to the FT.CREATE the same way that you support PREFIX {count} {prefix ...}. This way a user can choose to opt out of the default stopwords, or add their own based on their use case.