Modified the method in which save/restart data is propagated. The observation operator now handles its own start/restart files in its private directory, and
passes the information of data that is needed for a restart to the DaCycle through a list. This list gets appended by all methods, and at the end all files of that
list are copied to the restart/current directory. The contents of that directory replace the restart/one-ago directory at the end of the cycle.