added recalculate button and fixed handling use,j,jerr change events #237
added recalculate button and fixed handling use,j,jerr change events #237

NMGRL/pychron,UManPychron/pychron,UManPychron/pychron,USGSDenverPychron/pychron,NMGRL/pychron,USGSDenverPychron/pychron,UManPychron/pychron,USGSDenverPychron/pychron,UManPychron/pychron,NMGRL/pychron,USGSDenverPychron/pychron,NMGRL/pychron