STANBOL-760: Major update to the Sentiment Summarization Engine: Engine supports not the detection of Phrases. Sentiments within phrases are combined using the Probabilistic sum := a+b-(a*b) ensuring that multiple positives sentiments appled to the same noun rise the sentiment value (instead of using the mean). The mean is still used when combining multiple sentiment phrases e.g. for the sentiment of a whole sentence or the document as a whole.

git-svn-id: https://svn.apache.org/repos/asf/stanbol/trunk@1451179 13f79535-47bb-0310-9956-ffa450edef68