RestartConfig is a first-class citizen of EclipseConfig rather than
being embedded in IOConfig. This narrows IOConfig's responsibility to
only that of paths file system definitions and interactions, and
RestartConfig to what and when to output the restart file.
* This class contains the following State methods
** getSchedule
** getIOConfig
** getInitConfig
** getSimulationConfig
** getSummaryConfig
* For better decoupling
* For future, ease the shared_ptr-ref transition