Several minor fixes to REBUS printout
Changed default printout options for REBUS to enable automatic extensive printout of rebus in equilibrium solutions. Improved printout of burnup in extended.summary from SUMRY1 file.
Additional work will be needed in the future to add testing of post-processing on SUMRY files (issue #75 ) - this should include extending REBUS-generated SUMRY files for fast fluence information.