Creating a visitor to manage the filters
Removing deprecated class / Adding new filter resources and references
Adding filter parameters

- Endpoint/graph;
- Thresholds.
Using coreferenceResolution parameter to select the corresponding filter
Reverting changes in SpotlightModel.scala
Moving SparqlExecuter property to Server.java
Using confidenceFilter only when thresholds are available
Renaming spotterThresholds<List> in Server.java to similarityThresholds<List>

This might lead to confusion. The spotter_thresholds.txt in the statistical backend are not the same as the similarityThresholds in the Lucene backend. Eventually, we might add similarityThresholds to the statistical backend, too. They are just a way of estimating confidence. The spotter_thresholds.txt in the statistical backend are weights for scores that go into deciding if a SF is annotated (spotter_weights.txt might actually be a better name for them)
Merge pull request #190 from sandroacoelho/issue183

Issue 183 - Adding filters to the statistical implementation and refactoring.