add checkpointing to dnest4adapter

src/hops/NestedSampling/DNest4Adapter.cpp

@@ -54,10 +54,19 @@ double hops::DNest4Adapter::proposal_log_likelihood() const {
 }
 
 void hops::DNest4Adapter::print(std::ostream &out) const {
-    for (long i = 0; i < proposal->getState().rows(); i++)
+    for (long i = 0; i < this->proposal->getState().rows(); i++)
         out << this->proposal->getState()(i) << " ";
 }
 
+void hops::DNest4Adapter::read(std::istream &in) {
+    hops::VectorType readState = this->proposal->getState();
+    for (long i = 0; i < readState.rows(); i++) {
+        in >> readState(i);
+    }
+    this->proposal->setState(readState);
+
+}
+
 std::string hops::DNest4Adapter::description() const {
     std::string description;
     auto parameterNames = proposal->getDimensionNames();

src/hops/NestedSampling/DNest4Adapter.hpp

@@ -49,6 +49,12 @@ namespace hops {
          */
         void print(std::ostream &out) const;
 
+        /**
+         * @Brief reads current state to stream
+         * @param in
+         */
+         void read(std::istream &in);
+
         /**
          * @Brief returns string with column names in csv format
          * @return