Granular construction of MhOptionsValues

Refactor in support of #569 to enable various layered
phases of constructing MhOptionsValues.  This mirrors work done in
EnvOptionsValues.

src/misc/src/Miscellaneous.C

@@ -616,3 +616,4 @@ template void QUESO::MiscCheckTheParallelEnvironment<QUESO::GslVector, QUESO::Gs
 template bool QUESO::MiscCheckForSameValueInAllNodes<bool>(bool&, double, QUESO::MpiComm const&, char const*);
 template bool QUESO::MiscCheckForSameValueInAllNodes<double>(double&, double, QUESO::MpiComm const&, char const*);
 template std::string QUESO::container_to_string(const std::set<unsigned int>& container);
+template std::string QUESO::container_to_string(const std::vector<double>& container);

src/stats/inc/MetropolisHastingsSGOptions.h

@@ -156,6 +156,15 @@ class MhOptionsValues
   /*! Extract options from MLSamplingLevelOptions to \c this.*/
   MhOptionsValues (const MLSamplingLevelOptions& ml_opts);
 
+  //! Set parameter option names to begin with prefix
+  void set_prefix(const std::string& prefix);
+
+  //! Set default values for parameter options
+  void set_defaults();
+
+  //! Given prefix, read the input file for parameters named "prefix"+*
+  void parse(const BaseEnvironment& env, const std::string& prefix);
+
   //! Destructor
   virtual ~MhOptionsValues            ();
   //@}
@@ -751,9 +760,7 @@ class MhOptionsValues
   //! Copies the option values from \c src to \c this.
   void copy(const MhOptionsValues& src);
 
-  // We pass the the passed environment to get access to the MPI ranks etc for
-  // sanity checks
-  void checkOptions(const BaseEnvironment * env);
+  void checkOptions();
 
   friend std::ostream & operator<<(std::ostream & os,
       const MhOptionsValues & obj);