mfd updates; cluster dev

src/main/java/gov/usgs/earthquake/nshmp/data/Sequences.java

...n/java/gov/usgs/earthquake/nshmp/geo/json/Properties.java

src/main/java/gov/usgs/earthquake/nshmp/mfd/Mfd.java

src/main/java/gov/usgs/earthquake/nshmp/mfd/Mfds.java

...va/gov/usgs/earthquake/nshmp/model/ClusterRuptureSet.java

...ain/java/gov/usgs/earthquake/nshmp/model/Deserialize.java

...java/gov/usgs/earthquake/nshmp/model/FaultRuptureSet.java

...ain/java/gov/usgs/earthquake/nshmp/model/FaultSource.java

...main/java/gov/usgs/earthquake/nshmp/model/GridLoader.java

...ain/java/gov/usgs/earthquake/nshmp/model/HazardModel.java

.../gov/usgs/earthquake/nshmp/model/InterfaceRuptureSet.java

...java/gov/usgs/earthquake/nshmp/model/InterfaceSource.java

src/main/java/gov/usgs/earthquake/nshmp/model/MfdConfig.java

src/main/java/gov/usgs/earthquake/nshmp/model/ModelData.java

...main/java/gov/usgs/earthquake/nshmp/model/ModelFiles.java

...ain/java/gov/usgs/earthquake/nshmp/model/ModelLoader.java

src/main/java/gov/usgs/earthquake/nshmp/model/ModelUtil.java

...n/java/gov/usgs/earthquake/nshmp/model/SourceFeature.java

src/main/java/gov/usgs/earthquake/nshmp/package-info.java

src/main/java/gov/usgs/earthquake/nshmp/tree/LogicTree.java