VE-1497: Allow for case insensitive article name match

https://wikia-inc.atlassian.net/browse/VE-1433
https://wikia-inc.atlassian.net/browse/VE-1497
Not very often - only specific case in not popular use case in VisualEditor. In the meantime I will have a follow up with Platform + Data/API to figure out more proper facility for queries like this one.