added methods to retrieve trackers from the chase

...r/boreal/explanation/GRI/dynamicProcessing/RELTracer.java

...r/boreal/explanation/GRI/staticProcessing/GRIBuilder.java

...l/explanation/ruleFactories/RuleTransformationRecord.java

...l/explanation/ruleFactories/StaticGRIRuleTransformer.java

.../chasingAndTracing/ChaseStaticGRIRuleTransformerTest.java

...eal/test/explanation/chasingAndTracing/RELTracerTest.java

...lanation/solvingViaGMUS/FactSupportKBGSATEncoderTest.java

...oreal/test/explanation/solvingViaGMUS/GMUSSolverTest.java

...l/test/explanation/solvingViaGMUS/GMUSTranslatorTest.java

.../test/explanation/solvingViaGMUS/KBtoGSATEncoderTest.java

.../explanation/solvingViaGMUS/sat4j/MUSSat4JSolverTest.java

...rward_chaining/chase/lineage/FederatedLineageTracker.java

...boreal/forward_chaining/chase/lineage/LineageTracker.java

...al/forward_chaining/chase/lineage/LineageTrackerImpl.java

...real/forward_chaining/chase/lineage/NoLineageTracker.java