added nodisplay and graph_format options and applied to prior plots and graphs...

added nodisplay and graph_format options and applied to prior plots and graphs in estimstion routine. Tex tables also splitted when more than 50 params are estimated.

nograph: no figure is done
nodisplay: plots are done behind the scenes
graph_format: default only eps figs are saved. it accepts cell vector like {'eps','pdf','fig'}