Revisit default full-text stopword list

[RocketMan]

The default full-text stopword list is quite large:

https://dev.mysql.com/doc/refman/8.0/en/fulltext-stopwords.html#fulltext-stopwords-stopwords-for-myisam-search-indexes

Unfortunately, it contains many words which are significant in the identification of music-related material.

I propose we override the default stopword list with the much smaller stopword list that is used by default for InnoDB search indexes:

https://dev.mysql.com/doc/refman/8.0/en/fulltext-stopwords.html#fulltext-stopwords-stopwords-for-innodb-search-indexes

Given that zookeeper is not a massive database, the overhead to index the extra words should not present a storage or performance problem.

[RocketMan]

The kzsu production configuration has been updated and the indexes rebuilt.

The list of stopwords in kzsu prod as of 2020-07-31

In addition, the minimum full text word length has been reduced from 4 characters to 3.