VE-1389 Script to transition some users to VisualEditor

https://wikia-inc.atlassian.net/browse/VE-1540

/cc @SQLReview 
@mklucsarits Usually we try to avoid writing SQL queries "by hand", we have WikiaSQL (FluentSQL) and MediaWiki abstraction layer as well. Both allow you for performing joins between tables and take care of escaping parameters correctly.