Incorrect solr data > reimplement solr optimize

[rengaw83]

In 0ef148e the solr index optimization was removed.
Since version 9.5.4 no solr core optimization is performed anymore.

The optimize should be reimplemented and performed after each indexing process.

There are some problems with an unoptimzed index.
Apart from the performance, deleted indexes are not removed and we get incorrect data from solr.
problem example:

• facets depending on categories
• add category to database entry
• index entry
• category shows up in facetts
• category was removed from dbentry
• reindex entry
• category is still present in facets, but with zero results

After an manualy optimize category is not present in facets anymore.