StringFilter not correctly handling all negative search types

[markbeazley]

When the StringFilter applies the restriction here it uses orX for every type but TYPE_NOT_EQUAL for which andX is used.

I think andX needs to be used for at least some of if not all of the negative/inverted types, at least TYPE_NOT_CONTAINS and TYPE_NOT_IN.

As an example from Sylius, the product admin grid has a string search on product.code and product.translations.name, if the user picks TYPE_NOT_CONTAINS and searches for Shirt you get a where clause like this WHERE product.code NOT LIKE '%Shirt%' or product.translations.name NOT LIKE '%Shirt%' which would return every product where either the code or the name don't contain the search term, for example say every product just has a numeric code, every code will be true for NOT LIKE '%Shirt%' so every product will be returned.

The bug and any fix will only effect any filters which target multiple fields.

I can look at creating a PR, as it should a a pretty easy fix (just change the if to an in_array check of negative types), the tricky bit (at least to me) is figuring out which types exactly should be switched, there are 3 additional ones I think are likely:

1. TYPE_NOT_CONTAINS - pretty much needs to be as I think in most cases this is going to give wrong results
2. TYPE_NOT_IN - similar to 1
3. TYPE_NOT_EMPTY - I can see this one perhaps working both ways