Stop filter problem: enablePositionIncrements=false is not supported anymore as of Lucene 4.4 as it can create broken token streams

[1zaak (Izaak Khaliq)]

There is a 'fillter_token' that is configurable in the shingle token filter. The default is "_". I believe we can change it to "" so that it's empty if it encounters any stop words. Not sure if this is the best practice though.