HunspellStemFilter returns another values than Hunspell in console / command line with same dictionaries. [LUCENE-7378]

HunspellStemFilter for hungarian language returns different results than hunspell command for the same dictionary.

- input text is "kakaó"
- HunspellStemFilter results are "kakaó" and "kaka"
- "kaka" is wrong, it shouldn't be returned
- hunspell command returns "kakaó" only.

---
Migrated from [LUCENE-7378](https://issues.apache.org/jira/browse/LUCENE-7378) by Barta Tamás
Parent: #5379
Environment:
```
Apache Solr 5.4.1
```

Attachments: [hu_HU.aff](https://apache.github.io/lucene-jira-archive/attachments/LUCENE-7378/hu_HU.aff), [hu_HU.dic](https://apache.github.io/lucene-jira-archive/attachments/LUCENE-7378/hu_HU.dic)

Start with HunspellStemFilter and reproduce the Hungarian case using the attached hu_HU.aff and hu_HU.dic dictionaries and input "kakaó". Compare its stems with the hunspell command-line result; done when the filter no longer returns the incorrect "kaka" value and retains "kakaó".

Written by the indexing model from the issue text.