Fulltextsearch: disable lucene syntax flag

[alfonso-noriega]

While doing real time fulltext search, many times Lucene special characters are part of the input text and break the elastic/solr parser internally (non closed quotes, etc.) or return a complete set of wrong results(!,-,etc.).
To avoid this add a flag to FulltextSearch definition which allows to disable lucene syntax(by escaping special characters) in those use cases where there is no interest on using this advanced features.